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Interstellar Hydrogen Prevents Light-Speed Travel?

garg0yle writes "As if relativity wasn't enough to prevent us traveling at light speed, Professor William Edelstein of the Johns Hopkins University School of Medicine is now claiming that the interstellar hydrogen, compressed in front of the ship, would bring the journey to a shocking end. 'As the spaceship reached 99.999998 per cent of the speed of light, "hydrogen atoms would seem to reach a staggering 7 teraelectron volts," which for the crew "would be like standing in front of the Large Hadron Collider beam."'"

546 comments

  1. old news... by Anonymous Coward · · Score: 1, Insightful

    They already figured this out nearly a hundred years ago.

    1. Re:old news... by Geoffrey.landis · · Score: 4, Informative

      They already figured this out nearly a hundred years ago.

      In fact, erosion by interstellar matter (both hydrogen and dust) was a major plot element in Arthur C. Clarke's 1986 novel The Songs of Distant Earth.

      A while back, at the old 1994 Planetary Society conference on Interstellar Flight, I had a paper proposing a plasma erosion shield to protect an interstellar spacecraft-- I ought to dig that one up and put it on the web somewhere, but New Scientist ought to know about it, since they mentioned it in an article back in 1995.

      --
      http://www.geoffreylandis.com
    2. Re:old news... by Philip+K+Dickhead · · Score: 4, Funny

      Thereby increasing, almost infinitely, the improbability of any FTL technology - thusly ensuring success for a system that harnesses improbability as a motive power.

      --
      "Speaking the Truth in times of universal deceit is a revolutionary act." -- George Orwell
    3. Re:old news... by AmigaMMC · · Score: 5, Funny
      >As the spaceship reached 99.999998 per cent of the speed of light, "hydrogen atoms would seem to reach a staggering 7 teraelectron volts," which for the crew "would be like standing in front of the Large Hadron Collider beam

      ...

      Since most of the time the LHC is down that doesn't seem like a big problem :-p

      Ok, big fan of the LHC, but just had to say it

    4. Re:old news... by interkin3tic · · Score: 2, Insightful

      Since most of the time the LHC is down that doesn't seem like a big problem :-p

      Not to mention, does that comparison mean anything to anyone else? I've never stood in front of the LHC personally and don't know anyone who has. I can -assume- it wouldn't be healthy, but... well, it doesn't really ring home with me. It's not like "Oh shit, interstellar FTL would be like standing in front of the LHC? Well the last time I did that, I got horrible hemorrhoids. Good to know. Note to self: do not drive faster than light to a nearby solar system."

      How hard would it have been to make a more visceral if less accurate car metaphor. "99.999998 percent of the speed of light through hydrogen atoms would be like trying to drive your car at 90 miles an hour into a concrete wall." ...although I haven't done that either recently...

    5. Re:old news... by Anonymous Coward · · Score: 0

      Well, the comparison given for the CERN collider is being hit by a 100mph baseball. It could be fatal if you take it in the head or chest. You'll live if it hits you anywhere else, though you'll have a nasty bruise and maybe a burn. The LHC is bigger.

    6. Re:old news... by Marsala · · Score: 1, Informative

      Yeah, it's kind of hard to find something with which to relate.

      Maybe... "For the crew, it would be like getting ganked by 7,000,000,000,000 retadins (or 7 terarets) in WoW, all at once."

    7. Re:old news... by rpresser · · Score: 2, Interesting

      Is this it, Dr. Landis?

      http://www.islandone.org/Settlements/MagShield.html

      Magnetic Radiation Shielding: An Idea Whose Time Has Returned?
      Geoffrey A. Landis

      Presented at the Tenth Biennial SSI/Princeton Conference on Space Manufacturing
      May 15-19, 1991, Princeton, N.J.
      posted with permission of author

    8. Re:old news... by rpresser · · Score: 1

      non sequitur in the extreme.

    9. Re:old news... by chibiace · · Score: 0

      harry is that you?

      --
      he who controls the spice controls the universe
    10. Re:old news... by DRJlaw · · Score: 1

      Not to mention, does that comparison mean anything to anyone else? I've never stood in front of the LHC personally and don't know anyone who has. I can -assume- it wouldn't be healthy, but... well, it doesn't really ring home with me.

      Reading this reminded me that I had recently read about the nasty effects of the LHC on any target unlucky enough to get in its way. Apparently particle physicists are just waiting for something to stumble in front of this unreasonably large, essentially unaimable sci-fi-esque weapon. To wit:

      The collider's own prodigious energies are in some way its worst enemy. At full strength, the energy stored in its superconducting magnets would equal that of an Airbus A380 flying at 450 miles an hour, and the proton beam itself could pierce 100 feet of solid copper.

      Source

      How hard would it have been to make a more visceral if less accurate car metaphor. "99.999998 percent of the speed of light through hydrogen atoms would be like trying to drive your car at 90 miles an hour into a concrete wall." ...although I haven't done that either recently...

      Because the car is not going to punch a small, hot hole into the concrete wall, and the 99 walls behind it. I suspect the point that was being made, and was edited out, is that you're not going to be able to shield a living person from things that will impact the vessel with those sorts of energies.

    11. Re:old news... by Anonymous Coward · · Score: 0

      In fact, erosion by interstellar matter (both hydrogen and dust) was a major plot element in Arthur C. Clarke's 1986 novel The Songs of Distant Earth.

      Really? I don't remember that. It's been a while since I read it, but I only remember it being about a mostly ocean-covered planet that a human "seed ship" had found and populated with humans (not very many, as there wasn't much land mass). Eventually, a ship from Earth arrived with sleeping humans, the last of the race from Earth. A few woke up to check out the place and say hi, found that there wasn't any room there for so many human colonists, spent some time gathering supplies and fuel. I believe they needed ice for some reason, I forget why---ah yes! They needed ice as an ablative shield to continue their journey.

      Thanks for that.

      Posting anonymously so I don't look like an idiot.

      Another interesting thing in that book was that the ship used quantum fluctuation power, basically like the "ZPM" in Stargate, and which most scientists deride as "free energy" BS.

    12. Re:old news... by Grishnakh · · Score: 1

      The problem remains, as noted in the article, of any micrometeors floating around in space. If the ship hits a 10-gram micrometeor, that results in a 1 kT explosion.

      The solution to this is simple, however: you just need to put a deflector shield on the front of the ship.

    13. Re:old news... by Geoffrey.landis · · Score: 1

      Actually, that's a different one. (Some similarities, though).

      --
      http://www.geoffreylandis.com
    14. Re:old news... by Anonymous Coward · · Score: 0

      Your cut. Where the hell is my pizza analogy?

    15. Re:old news... by Zarf · · Score: 1

      I am a strange loop.

      --
      [signature]
    16. Re:old news... by exploder · · Score: 2, Informative

      Not to mention, does that comparison mean anything to anyone else? I've never stood in front of the LHC personally and don't know anyone who has.

      Talk to this guy.

      --
      Yo dawg, I heard you like the Ackermann function, so OH GOD OH GOD OH GOD
    17. Re:old news... by pdabbadabba · · Score: 1

      Ironically modded "informative"...

    18. Re:old news... by Anonymous Coward · · Score: 0

      The best description I've ever come across of the LHC's energy levels is a description of what the beam dump must endure:

      "while the beam dump must absorb 362 MJ (87 kilograms of TNT) for each of the two beams. These immense energies are even more impressive considering how little matter is carrying it: under nominal operating conditions (2,808 bunches per beam, 1.15×1011 protons per bunch), the beam pipes contain 1.0×109 gram of hydrogen, which, in standard conditions for temperature and pressure, would fill the volume of one grain of fine sand." from the LHC Wikipedia article.

      Or even better is:
      "Each of the circulating beams of the proposed Large Hadron Collider (LHC) will contain up to 4.7 x 10^14 protons at an energy of 7.7 TeV, giving a maximum stored energy per beam of 583 MJ [l]. The LHC beam dumping system must be able to accommodate this energy. Graphite has been chosen for the principal energy absorbing material because of its very favorable physical properties [2]. Sweeping the beam over the front face of the dump alone is insufficient unless the tunnel leading to the dump is lengthened well beyond its proposed 750 m, or the performance of the kicker magnets which sweep the beam are pushed to unrealistic levels. Assuming 22OO“C as the maximum tolerable temperature rise for the graphite core and a sweeping radius in the range 5 to 10 cm a further reduction in the peak energy density of the order of a factor of 3 or more is required if reasonable safety factors are to be applied."
      http://epaper.kek.jp/e92/PDF/EPAC1992_1545.PDF

    19. Re:old news... by Anonymous Coward · · Score: 0

      It would be like crossing the streams.

    20. Re:old news... by OeLeWaPpErKe · · Score: 1

      Because the car is not going to punch a small, hot hole into the concrete wall, and the 99 walls behind it. I suspect the point that was being made, and was edited out, is that you're not going to be able to shield a living person from things that will impact the vessel with those sorts of energies.

      Of course you are ... you just make sure it hits a "cushion" that spreads the impact force around. People survive getting slammed into a concrete wall at 90 mph regularly, it's called an airbag.

      Oone suggestion I've heard before is to attempt to transfer the impact force into a magnetic field. We cannot currently do that, but there are, for example, plans to make a material that consists of 2 superconductors with a thin layer between them, each directing massive electrical energy in the opposite direction. This would create a situation where anything that wishes to punch a hole in the material would have to exert more force than the electrical field exerts on the material, effectively meaning that this material can be made as strong as you want. And yes, this is not practical, the material in between them would get squashed beyond any material's carrying capacity, and ... but surely there are ways to make something like this happen.

      Another suggestion heard often is to keep a hot plasma cloud in position with a magnetic field. This would produce an effect very much like the shields around "starship" type ships. Any impact on the cloud would immediately cause very fast moving streams within very hot gas, focused on the impact point, making life very uncomfortable for whatever's attempting to pierce the "shield". Of course, such a shield would not be (entirely) transparent, and you can't just project it anywhere. It would also presumably heat up whatever room it's in very fast (or at least, the cigarette box sized versions, capable of stopping the average ant most of the time, the ones that exist today do).

      Or you could just drop the gas entirely, and merely keep a very strong magnetic field going directly. Like the tokamak nuclear fusions reactors do. It is very hard to pierce that magnetic field. Hard enough to prevent a > 5 million degree gas on one side from heating up whatever's on the other side of the field. Getting within a meter distance from a 5 million degree gas cloud will kill any human, but you can comfortably put your hand on the walls of a tokamak reactor at less than 30cm distance from that same gas (but you'll have to make sure the 1.2 tesla magnetic field doesn't throw you across the room, remember to remove your cell phone). Presumably, with an actually working energy source this field can be made a lot stronger, and encompass an entire starship (heh, if they got fusion working in the first place, it would become a whole lot easier to produce a working tokamak reactor. I mean if you could just "order" a 50 gigawatt pulse of 2-3 seconds from the grid, the problem of starting a fusion reaction would become a whole lot less messy).

    21. Re:old news... by Jarik+C-Bol · · Score: 1

      Wow. That has to be the most educational post on /. i've read in a month of sundays. thank you.

      --
      I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
    22. Re:old news... by Marxist+Hacker+42 · · Score: 1

      But at that energy level, has anybody thought that perhaps instead of a problem, this might actually be the *solution* to FTL travel- an adaptation of ramjet tech, compressing the incoming hydrogen (and whatever other matter happens to be there) and incinerating it into a much faster outgoing stream?

      --
      SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    23. Re:old news... by geoskd · · Score: 1

      Not to mention, does that comparison mean anything to anyone else? I've never stood in front of the LHC personally and don't know anyone who has.

      Think gigantic laser beam, that uses the entire output of a nuclear power plant for its power source, and you're on the right track.

      -=Geoskd

      --
      I wish I had a good sig, but all the good ones are copyrighted
    24. Re:old news... by rhyder128k · · Score: 2, Funny

      As an added benefit, the polarity of such a deflector could be reversed to solve all sorts of problems that might crop up.

      --
      Michael Reed, freelance tech writer.
    25. Re:old news... by Grishnakh · · Score: 1

      Exactly. When in doubt, just reverse the polarity and that should fix your problems. But sometimes that doesn't work, and you might need to check the Heisenberg compensators.

    26. Re:old news... by dougmc · · Score: 1
      http://en.wikipedia.org/wiki/Anatoli_Bugorski

      ... it wasn't the LHC, but it still screwed him up pretty nicely, even if it didn't kill him.

      The LHC analogy is a pretty good one, though it's not clear how dense the beam is in the LHC vs. what would be found in outer space -- it's probably more dense in the LHC.

      And yes, the anonymous coward who said this is old news is absolutely right -- it's been discussed in science fiction for decades now, usually with some sort of shield that protects people and perhaps even collects the hydrogen for use in the spacecraft's fusion engines.

    27. Re:old news... by Ihmhi · · Score: 1

      Sounds like the Navigational deflector for a starship in the Star Trek universe.

      The navigational deflector (also called the deflector dish, the deflector array or the nav deflector) is a component of many starships, and is used to deflect space debris, asteroids, microscopic particles and other objects that might collide with the ship. At warp speed the deflector is virtually indispensable for most starships as even the most minute particle can cause serious damage to a ship when it is traveling at superluminal velocities.

      Star Trek may be filled with inanity and loads of technobabble, but it does occasionally have a sound basis in science.

      As an aside, I've always wondered what the current state of plasma research is. When can I get me a plasma force field for my home, or my own personal lightsaber/hedge clipper/daughter's boyfriend intimidation unit?

    28. Re:old news... by budgenator · · Score: 1

      . It's not like "Oh shit, interstellar FTL would be like standing in front of the LHC? Well the last time I did that, I got horrible hemorrhoids. Good to know. Note to self: do not drive faster than light to a nearby solar system."

      Well actually they are not talking about FTL, but relativistic subluminal velocities, if you were traveling faster than the speed of light, then the hydrogen would become imaginary. I think the article is assuming that you would accelerate from a resting velocity to a superluminal velocity, but that is impossible.

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    29. Re:old news... by Anonymous Coward · · Score: 0

      This fellow would have some idea...

      http://forgetomori.com/2008/science/hit-by-a-particle-accelerator-beam/

    30. Re:old news... by Anonymous Coward · · Score: 0

      "I can -assume- it wouldn't be healthy, but... well, it doesn't really ring home with me. It's not like "Oh shit, interstellar FTL would be like standing in front of the LHC?"

      Maybe this article might help. It talks about the beam power in terms of how long it would take to defrost a pizza (approximately 30 nanoseconds if the energy were diffused over the whole pizza, but it's also time-averaged to account for the pulsed nature of the beam).

    31. Re:old news... by The_Wilschon · · Score: 1

      You'd also find that you had trouble from the 27 kilo-Kelvin blackbody radiation that the 2.728 Kelvin CMBR would get blueshifted into.

      --
      SIGSEGV caught, terminating

      wait... not that kind of sig.
    32. Re:old news... by Anonymous Coward · · Score: 0

      Got it nice and hot, right here

    33. Re:old news... by Anonymous Coward · · Score: 0
    34. Re:old news... by bahamat · · Score: 1

      That's what the navigational deflector shield is for!

    35. Re:old news... by tcolberg · · Score: 1

      If only you could miniaturize that proton beam / nuclear accelerator into something the size of a backpack. Then you could go around busting things like... copper.

  2. Fuckin' Noobs by jim_v2000 · · Score: 5, Funny

    That's what the deflector array is for.

    --
    Don't take life so seriously. No one makes it out alive.
    1. Re:Fuckin' Noobs by captaindomon · · Score: 4, Informative

      Not to mention the Bussard Collectors.

      --
      Just because I can hook a shark from a boat, I do no offer to wrestle it in the water.
    2. Re:Fuckin' Noobs by Rogerborg · · Score: 1

      ...and how would you get to Ludicrous Speed without them?

      --
      If you were blocking sigs, you wouldn't have to read this.
    3. Re:Fuckin' Noobs by oldhack · · Score: 1

      Take it easy. The guy works at the school of quackery, for god sake.

      --
      Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
    4. Re:Fuckin' Noobs by Joce640k · · Score: 4, Insightful

      UM, I thought the plan was to scoop them up and use them for fuel, ie. you WANT those hydrogen atoms to pile up in front of the ship.

      --
      No sig today...
    5. Re:Fuckin' Noobs by Austerity+Empowers · · Score: 1

      Or is that Buzzard Collectors?

      True story, a friend liked to take his muscle car out to race on a deserted road in the country. One particular day there was some dead something on the side of the road with a bunch of buzzards doing their thing. Long story short, it turns out the fender of a Pontiac Firebird is a Buzzard Collector.

    6. Re:Fuckin' Noobs by Anonymous Coward · · Score: 0

      Hell if what he's saying is true, you could use the hydrogen for fuel and power the internals of the ship off the charge collecting on the front of it somehow!

    7. Re:Fuckin' Noobs by Anonymous Coward · · Score: 0

      This is where you deploy the redirectors. To capture that energy and use it.

    8. Re:Fuckin' Noobs by mseidl · · Score: 1

      I like the tan I get in the lhc.

    9. Re:Fuckin' Noobs by Narpak · · Score: 1

      UM, I thought the plan was to scoop them up and use them for fuel, ie. you WANT those hydrogen atoms to pile up in front of the ship.

      As I understand it for a Ramscoop type system you want those hydrogen atoms. However a ramscoop is meant to travel at sub-lightspeed. Presumably for faster than light you might want something that phases out, teleports, or whatever; to avoid hitting a small meteor and getting a large hole in your ship (I am presuming that hitting a rock at 500.000 m/s is bad).

    10. Re:Fuckin' Noobs by Joce640k · · Score: 1

      At the speed of light you'll be infinitely thin so a rock will pass right through you, no problem.

      --
      No sig today...
    11. Re:Fuckin' Noobs by rssrss · · Score: 4, Informative

      The Bussard Collector is part of a Bussard Ramjet.

      The Bussard ramjet is a system of spacecraft propulsion proposed in 1960 by the physicist Robert W. Bussard. A moving spacecraft would use enormous electro-magnetic fields to collect and compress hydrogen from the interstellar medium. The hydrogen would be forced into a progressively constricted magnetic field, which would compress it until thermonuclear fusion occurs. The magnetic field would then direct the heated gas in the direction opposite to the intended direction of travel, thereby accelerating the vessel.

      More generally.

      --
      In the land of the blind, the one-eyed man is king.
    12. Re:Fuckin' Noobs by TooMuchToDo · · Score: 1

      Nice. And so the interstellar ramjet is invented. Fame me! =)

    13. Re:Fuckin' Noobs by arth1 · · Score: 1

      Um, of course it's designed for traveling sub-lightspeed. Everything is, because "speed" loses its meaning at exactly the speed of light.
      "FTL" belongs in pulp sci-fi. Let's keep it there.

    14. Re:Fuckin' Noobs by bill_mcgonigle · · Score: 1

      Not to mention the Bussard Collectors.

      How can I get a job taking items from the 80's ST:TNG technical manual, figuring out why they're there, and then publishing a press release stating X is impossible because of it?

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    15. Re:Fuckin' Noobs by Anonymous Coward · · Score: 0

      Easily. You write a book and if its good enough a publisher will take care of it.

    16. Re:Fuckin' Noobs by Anonymous Coward · · Score: 1, Insightful

      Anything that gets sucked into the 'engine' isn't going to be colliding with superstructure or crew like a blast from a particle accelerator.
      In essence, a highly efficient Bussard Ramjet design would also be a highly efficient defense from that hydrogen bombardment.

    17. Re:Fuckin' Noobs by OctaviusIII · · Score: 1

      Close! The deflector field is specially tuned to deflect anything except for a certain number of hydrogen atoms per second, adjusting itself based on the ship's needs and with safeties in place. The ramscoop would divert hydrogen atoms that are allowed through the field to the engines and storage tanks.

      --
      What's this? Another weblog? On transit?
    18. Re:Fuckin' Noobs by Gilmoure · · Score: 1

      My '72 Nova grill was good for crows.

      --
      I drank what? -- Socrates
    19. Re:Fuckin' Noobs by Gilmoure · · Score: 1

      Star Trek? Bussard Ramjets were popularized by Larry Niven.

      --
      I drank what? -- Socrates
    20. Re:Fuckin' Noobs by Anonymous Coward · · Score: 0

      The guy is a prof in a Medical school. What does he know about physics!?

    21. Re:Fuckin' Noobs by bondsbw · · Score: 1

      We look for things, things that make us go. Do not try to trick us. We can tell.

      * Beholds the Crimson Forcefield *

      They are strong now...

      --
      All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
    22. Re:Fuckin' Noobs by kurzweilfreak · · Score: 1

      The way I understood it was the interstellar hydrogen wasn't an issue at warp speeds because of the nature of warp drive. From what I understood, warp drive created "subspace bubbles" or "warp bubbles" that literally warped space in front of and behind the ship by making space smaller in the front and larger in the back, thus propelling the ship forward. Because the ship itself never actually traveled faster than light relative to the space it was in, but that the space around it is what changed, faster than light travel was possible without violating relativity.

      If that's the case, then I would assume that as the space around the ship warps, so does any interstellar hydrogen along with it, so the hydrogen is never actually in the ship's way but is pushed out of the way by the warped space, almost as if the ship were tunneling "through" space.

      --

      kurzweil_freak

      5th Kyu Genbukan Ninpo/KJJR student

      Be the darkness that allows the light to shine.

    23. Re:Fuckin' Noobs by Weedhopper · · Score: 2, Informative

      The guy is a prof in a Medical school. What does he know about physics!?

      Because the guy's a Harvard trained PhD physicist with relevant research interests, who also happens to be teaching at the Department of Radiology at Hopkins, that's why.

    24. Re:Fuckin' Noobs by kurzweilfreak · · Score: 1

      Sorry for replying to my own message, but I see now that someone below linked to the article that describes how warp drive works. Beat me to it. *grumble*

      --

      kurzweil_freak

      5th Kyu Genbukan Ninpo/KJJR student

      Be the darkness that allows the light to shine.

    25. Re:Fuckin' Noobs by bill_mcgonigle · · Score: 2, Informative

      Star Trek? Bussard Ramjets were popularized by Larry Niven [larryniven.org].

      Yes, this thread started on deflector dishes, a 'trek tech. Then Bussard Collectors were added in a reply, also a 'trek tech. They're not funneling the hydrogen at speed into a fusion reactor, merely collecting it, but they do use it to mitigate the interstellar gas pressures that are the subject of TFA.

      If you really want to split hairs, Tau Zero pre-dates the Niven works by a few years.

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    26. Re:Fuckin' Noobs by stuckinphp · · Score: 1

      burn?

      --
      if only
    27. Re:Fuckin' Noobs by haruchai · · Score: 1

      Work in academia; apply for a federal grant

      --
      Pain is merely failure leaving the body
    28. Re:Fuckin' Noobs by CodeBuster · · Score: 1

      Reversing the polarity of the inertial dampers should compensate for any excess tachyon radiation encountered when speeds exceed warp two.

    29. Re:Fuckin' Noobs by Trogre · · Score: 1

      You're thinking of the shuttlecock, I mean, ramscoop in front of Red Dwarf.

      --
      "Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
    30. Re:Fuckin' Noobs by budgenator · · Score: 1

      The synchrotron radiation would still fry you

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    31. Re:Fuckin' Noobs by Anonymous Coward · · Score: 0

      If I was traveling at 99.9% the speed of light, I could have First Post on Slashdot every time, but to observers, the forum would be closed before it ever showed up!!!

    32. Re:Fuckin' Noobs by TangoMargarine · · Score: 1

      Let me know if you're willing to test that theory personally :-)

      --
      Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
    33. Re:Fuckin' Noobs by jayveekay · · Score: 1

      Has anyone told Kevin Smith of this? He'll want to know!

    34. Re:Fuckin' Noobs by Hal_Porter · · Score: 1

      Not if you're a ROBOT.

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    35. Re:Fuckin' Noobs by Hal_Porter · · Score: 1

      No you fool! You need to remodulate the shield harmonics and reverse the polarity of the neutron flow! What are you trying to do, kill us all?

      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
    36. Re:Fuckin' Noobs by DamienNightbane · · Score: 1

      In this case, I think it would be more akin to a Bussard Scramjet.

    37. Re:Fuckin' Noobs by LINM · · Score: 1

      That is if you go with outdated technology. Any interstellar traveler worth their dust would of course use a Cochran field generator.

      --

      Hunger is the best sauce.

    38. Re:Fuckin' Noobs by RivenAleem · · Score: 1

      If you really want to split hairs,

      It's a fusion reactor, FUSION.

  3. Damn it, now they tell me by verbalcontract · · Score: 5, Funny

    And I was just about to get into my 99.999998% lightspeed spaceship.

    1. Re:Damn it, now they tell me by Yvan256 · · Score: 1

      Wave goodbye when I depart in my 99.999997% lightspeed spaceship!

    2. Re:Damn it, now they tell me by pla · · Score: 4, Insightful

      And I was just about to get into my 99.999998% lightspeed spaceship.

      Aside from the current nonexistence of such a craft, that really does count as the faulty premise with Edelstein's conclusion...

      Why would you go that fast (presuming you can't go much faster, of course)? It takes exponentially more energy to accelerate as you approach the speed of light, but that doesn't get you to your destination all that much faster. At a mere 99.9% of the speed of light, you spend less than one extra hour of travel (externally measured, of course) per month. For a "realistic" trip to nearby stars, that means an extra day and a half out of the 4.37 years to get to Alpha Centauri.

      For relatively local trips, the difference amounts to a triviality - And longer trips simply will never happen unless we have some breakthrough that makes Star-Trek-like warp engines a reality.

    3. Re:Damn it, now they tell me by dominious · · Score: 1

      hey i thought the faster you travel the slower the time goes for you? 4 years is for those who are not traveling at near the speed of light. no? IANAP

    4. Re:Damn it, now they tell me by Syberz · · Score: 2, Funny

      Dangerous perhaps, but if there's a chance we can get Fantastic 4 like powers when it happens then I'm in... well, unless I could turn into the Thing and that would just suck http://www.cad-comic.com/cad/20050304/#n629.

      --
      ~Syberz
    5. Re:Damn it, now they tell me by hasdikarlsam · · Score: 3, Insightful

      I don't see how that is an advantage.

      If you go faster, you get less time to do.. whatever you'd want to do during the flight. If you <i>want</i> to work slower, slow down the computer running your brain.

      Oh, you were planning to go in a biological body? Shame on you, that will never happen when uploading makes it so much cheaper.

    6. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      Is this taking into account time dilation? 99.999998% of the speed of light makes time run 5000 times slower. By comparison, 99.9% of the speed of light is only 20 times slower.
      Excluding the amount of time it would take to accelerate to such velocities, it could make the difference between a generation ship and a short trip.

    7. Re:Damn it, now they tell me by Fnkmaster · · Score: 5, Insightful

      Well, the only material difference is the time dilation factor for the person in the spaceship. At 99.9% the speed of light, that factor is about 22 - i.e. the 4.4 years seems to take only about 0.2 years, or 10 weeks. At 99.999998% of the speed of light, it is almost exactly 5000 - which means the trip would seem to pass in about 7 hours. This is ignoring the general relativistic effects of acceleration and deceleration.

      So, it's a material difference to the person traveling, but not so material to the observer stationary relative to Alpha Centauri.

    8. Re:Damn it, now they tell me by dmartin · · Score: 3, Informative

      It really depends on what you think is relevant. For example if the purpose is to do research for people on Earth, you probably are interested (at least in part) in the time taken for the round trip, and how long people on Earth have to wait to see the benefits of their investment. If you are looking at colonization then you are probably more interested in the amount of time as experienced by the people travelling on the ship. In this case the difference between 99.9% of the speed of light, and 99.99% of the speed of light is significant.

      To make the example concrete, let us take your example of Alpha Centuri:
      Distance: ~ 4 light-years.

      • 99.9% of the speed of light:
        Time (Earth observer): 4 years and 1.5 days
        Gamma factor*: 22.4
        Time (Ship observer): 65 days
      • 99.99% of the speed of light:
        Time (Earth observer): 4 years and part of a day.
        Gamma factor*: 70.7
        Time (Ship observer): 20.5 days.

      So from the point of view of the *crew* the journey takes about a third the time, although from Earth you are correct in stating they are essentially the same.

      * The gamma factor, or time dilation factor (or length contraction factor), is given by special relativity. If you speed is v and the speed of light is c then
      Gamma factor = 1/sqrt(1-(v/c)^2)

    9. Re:Damn it, now they tell me by Angst+Badger · · Score: 2, Informative

      For relatively local trips, the difference amounts to a triviality

      For relatively local trips, especially considering that you have to spend half the trip turned around and decelerating, there's going to be a point well before nine-tenths of C that the cost of further acceleration vastly outweighs the value of getting to the destination faster. Without knowing what the cost of energy is going to be if and when we can build propulsion systems capable of relativistic travel, I couldn't say where the point of diminishing returns would be, but for in-system travel, I'd be willing to bet it's not even an appreciable fraction of C.

      Besides, it's a long, hard slog to Vland.

      --
      Proud member of the Weirdo-American community.
    10. Re:Damn it, now they tell me by Rubedo · · Score: 1

      I am a physicist.
      At 99.999998% the speed of light, the trip to Alpha Centauri would only take about 7 hours for those on the ship. For those on earth, it would still seem like 4.37 years. So it wouldn't help with interstellar commerce to go so fast, but for the purposes of colonization the extra speed makes a huge difference.

    11. Re:Damn it, now they tell me by Zordak · · Score: 1

      Why would you go that fast (presuming you can't go much faster, of course)? It takes exponentially more energy to accelerate as you approach the speed of light, but that doesn't get you to your destination all that much faster. At a mere 99.9% of the speed of light, you spend less than one extra hour of travel (externally measured, of course) per month. For a "realistic" trip to nearby stars, that means an extra day and a half out of the 4.37 years to get to Alpha Centauri.

      The issue is not the time for an external observer, it's the time for the folks in the ship. The same exponential increase in energy also equals an exponential decrease in time that you, the astronaut, have to spend cooped up in a ship. I remember reading somewhere that if you could keep accelerating so that the internal observer experienced a constant 1g, you could traverse the visible universe in something like a month (feel free to correct me if you have done the actual math). Sure, the rest of the universe will grow old around you, but in the meantime, you only had to pack one bag.

      --

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    12. Re:Damn it, now they tell me by trentblase · · Score: 1

      Why would I want to measure travel time externally? The closer you get to C, the shorter the distance to Alpha Centauri seems. And this dilation increases asymptotically as you approach C. So if I'm travelling at 99.999998% of C, and you're travelling at a mere 99.9%, you will age much faster during the same trip.

    13. Re:Damn it, now they tell me by osu-neko · · Score: 1

      So, it's a material difference to the person traveling, but not so material to the observer stationary relative to Alpha Centauri.

      Actually, that could make a vast difference to the person watching you from Alpha Centauri. In one case, that person watches you go through 10 weeks worth of food, other consumables, and power to keep you alive during the trip. In the other case, they watch you make the trip and have dinner at your destination, saving a lot of energy by not having to accelerate a ten week supply of food and such for you to use during the trip. At high enough speeds, you can pretty much forgo any kind of life-support, just fling a tin can with enough air in it to last the journey. It's not only a material difference, but one that potentially saves a lot of energy (albeit probably not enough to cover the cost accelerating to the faster rate).

      --
      "Convictions are more dangerous enemies of truth than lies."
    14. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      Of course, one neat thing is that someone on Alpha Centauri can plant a plot of food for the incoming colonists, and they could eat it when they arrive a few hours later. ;-)

    15. Re:Damn it, now they tell me by Hurricane78 · · Score: 1

      Silly you. As if that was the biggest problem.

      Your biggest problem will be to prevent whole star systems from falling into the black hole you would become in the process of accelerating a object with real mass like that. ;)

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    16. Re:Damn it, now they tell me by Tetsujin · · Score: 1

      Why would you go that fast (presuming you can't go much faster, of course)? It takes exponentially more energy to
      accelerate as you approach the speed of light, but that doesn't get you to your destination all that much faster. At a
      mere 99.9% of the speed of light, you spend less than one extra hour of travel (externally measured, of course) per month. For
      a "realistic" trip to nearby stars, that means an extra day and a half out of the 4.37 years to get to Alpha Centauri.

      Well, no, but it seems faster...

      --
      Bow-ties are cool.
    17. Re:Damn it, now they tell me by Grishnakh · · Score: 2, Insightful

      Yep, round-trip time from Earth is important. One-way time is only important if 1) you don't plan on returning home, and 2) you actually know where you're going. Without sending probes or whatever to various star systems, and getting data back from them showing what's there, then any one-way colonization ship isn't going to have a viable destination. It would spend way too much time jumping from star to star until you find something suitable.

    18. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      That dilation effect would help cut a two month journey to three weeks... saves on other costs like supplied or animation effects (meaning a lighter ship, so less energy cost for the speed needed)

    19. Re:Damn it, now they tell me by dlgeek · · Score: 1

      Or (as others have pointed out) 3.) You have a limited supply of consumables.

    20. Re:Damn it, now they tell me by Grishnakh · · Score: 1

      Why would I want to measure travel time externally? The closer you get to C, the shorter the distance to Alpha Centauri seems.

      Because that tells you how much all your friends and family back on Earth will have aged while you're gone. The less time passes externally, the longer all your friends will still be alive when you return.

      Of course, if you plan a one-way trip, this isn't a problem for you, but right now we don't know if there's anyplace livable in the Alpha Centauri system, and we won't know until someone or something has gone there physically and reported back. To find places worth traveling for human colonization, we have to send probes to various places, and wait for them to send back data. The faster these probes can travel (as perceived on Earth), the less time we'll all have to wait before we have a viable destination to send colonists.

    21. Re:Damn it, now they tell me by Zarf · · Score: 1

      The vaccume of space is mind numbingly boring to an organic or inorganic human... therefore faster is better. Even if it wasn't people always want to get where they are going. This is why people speed on the freeway. I predict even super human intelligences will speed.

      --
      [signature]
    22. Re:Damn it, now they tell me by Grishnakh · · Score: 1

      Don't forget that humans can be put into suspended animation to vastly reduce the amount of consumables. Seriously, we're pretty close already to being able to do this with people.

    23. Re:Damn it, now they tell me by Zarf · · Score: 1

      If airplane tickets worked like that I would spring for first class.

      --
      [signature]
    24. Re:Damn it, now they tell me by HiThere · · Score: 1

      considering that to go that tiny bit faster you need a much more powerful engine and a lot more fuel ... other consumables seem a much less significant limit.

      P.S.: I'm dubious about the Bussard Ramjet. The estimates I've seen says that it will encounter too much resistance to work properly above around 0.5 C. (Perhaps that should be "to work properly", but I can't remember where that study was, and what it's assumptions were. So I compromised.)

      OTOH, there's a guaranteed way to make the Bussard Ramjet work properly, but it requires carting along a large quantity of antimatter.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
    25. Re:Damn it, now they tell me by Zarf · · Score: 1

      You can get anywhere in the cosmos in 5 minutes (experiential) you just have to go fast enough.

      --
      [signature]
    26. Re:Damn it, now they tell me by KingTank · · Score: 0

      And I was just about to get into my 99.999998% lightspeed spaceship.

      Yeah, sounds worse than the Toyota recall, huh?

    27. Re:Damn it, now they tell me by amorsen · · Score: 3, Interesting

      Accelerating to 99.999998% of light speed in 3.5 hours would be a somewhat dizzying experience. Especially since you'd actually experience an acceleration equivalent to going to 5000 times light speed in a pure Newtonian universe. We're talking more than 500.000km/s^2 here -- or 50 million g.

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    28. Re:Damn it, now they tell me by trentblase · · Score: 1

      I usually take my family with me on my space trips. Also, if I send out a probe, I'll be dead by the time it gets back. If I fly from system to system at .9999999 C, I can actually live to see the colonization. (Yes, realize that a civilization that can send me from system to system at relativistic speeds probably has life-prolonging or stasis technology too... but the point is that there ARE reasons to travel that fast)

    29. Re:Damn it, now they tell me by Cassini2 · · Score: 1

      You might be forgetting acceleration and deceleration. At the high-Gs required to make the tin-can idea work, the tin-can would quickly become flattened. Of course, given usual design margins, the people inside would be flattened before the tin-can collapsed ...

      Also, I think the mass-dilation effects of traveling that close to the speed of light would probably have practical consequences that would not be pleasant. Any nearby object would have the mass of a black hole (or at least something very heavy). It would be difficult to fly straight. The total accelerated mass would be well in excess of the mass of the space ship. You would destabilize orbits of comets, which would not be nice either.

    30. Re:Damn it, now they tell me by Werrismys · · Score: 1

      Why would you go that fast (presuming you can't go much faster, of course)? It takes exponentially more energy to

      The problem is not the energy, the problem is the time dilatation. Once you go near-c, you can as well go very near c since you're dead to everyone you knew.

      --
      'Once scientists, even the dim-witted social scientists, get muzzled, the Western Civilization is finished.' - oldhack
    31. Re:Damn it, now they tell me by nomadic · · Score: 1

      Eh, with a long life and a suitably well-stocked ship, I don't know if it's a big deal.

    32. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      you'd actually experience an acceleration equivalent to going to 5000 times light speed

      Apples and oranges. Speed != acceleration.

    33. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      Which one applies? Does the observer in the space ship feel the g-force of accelerating in 3.5 hours, or the g-force of accelerating in 2.2 years? Though I suspect both would be more than an individual could handle. Sounds like we're going to need inertial dampeners for people to handle the trip.

    34. Re:Damn it, now they tell me by dryeo · · Score: 1

      I used to have a chart, presumably done by someone who knew the math.
      At 1 gee it was about 70 years to the edge of the observable universe.
      A month at one gee will get you to Pluto including spending half the trip decelerating.
      It takes about a year to accelerate enough to start getting much in the way of relativistic effects.

      --
      https://en.wikipedia.org/wiki/Inverted_totalitarianism
    35. Re:Damn it, now they tell me by TangoMargarine · · Score: 1

      So obviously an inertial damper will need to be developed, too. For comparison, the highest application of g forces that anyone has survived was ~45g. (Was there some story about somebody who fell out of an airliner at altitude and survived?)

      --
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    36. Re:Damn it, now they tell me by amorsen · · Score: 3, Funny

      Apples and oranges. Speed != acceleration.

      I simply omitted the "in 3.5 hours" which were in the previous sentence. I presumed my readers would be sentient.

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      Finally! A year of moderation! Ready for 2019?
    37. Re:Damn it, now they tell me by amorsen · · Score: 1

      In the space ship the total travel time is 7 hours, so the 2.2 years don't apply.

      Basically you can ignore relativity if you only care about what the space ship observes. If you want to fly 5000 times light speed, no problem, just keep accelerating. The rest of the world will see you stuck at slightly less than light speed, but that really isn't your problem, is it?

      --
      Finally! A year of moderation! Ready for 2019?
    38. Re:Damn it, now they tell me by tehcyder · · Score: 1

      I presumed my readers would be sentient.

      That's a dangerous assumption on the internet.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    39. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      For a "realistic" trip to nearby stars, that means an extra day and a half out of the 4.37 years to get to Alpha Centauri

      Only when measured on a clock/calendar that is not experiencing acceleration and is at rest with respect to the two stars. An Earth-based observer, despite experiencing accelerations and not being at rest, is a good approximation (her clock will run a few milliseconds a day slow compared to the idealized observer).

      However, the people inside the ship experience what they perceive as a Lorentz contraction of the distance to their destination. The distance is exponentially shortened as the relativistic speed limit is approached. The effect of this is that measuring by their own shipboard clocks the trip would take a lot less time at 0.99999998c than 0.99c. (The people on Earth and in orbit around Alpha Centauri would still think the rocket trip takes about 4.37 years, although the Earth observer would not know this until twice that time had elapsed). These observers would consider the clocks onboard the relativistic spaceship to have experienced a Lorentz time dilation, and also the ship itself (and any rulers onboard) would be length contracted.

      A special relativity treatment of this using the Lorentz-Fitzgerald formula is here: http://www.fourmilab.ch/cship/lorentz.html which is entirely accurate if you ignore accelerations experienced by the spacecraft.

      Unfortunately for a classical object with the mass of a spaceship general relativistic effects become harder to ignore as one approaches c, since the increasing mass-energy-momentum nontrivially influences the stress and pressure terms in the Einstein stress-energy tensor, which alters not only the geodesics of nearby classical objects (i.e., the high mass-energy causes the fast ship to develop a strong gravitational field) but also slows its onboard clocks (relative to the Earth and Alpha Centauri observers' clocks) too (and also shortens onboard rulers from those observers' perspectives too). That's OK, it makes the trip even shorter, but it also creates a rather nasty gravitational potential gradient that rapidly becomes unignorable at scales less than the size of the ship (so it would probably rip apart tidally). Also, any infalling objects would develop energy through gravitational time dilation (i.e., infalling photons blueshift, infalling electrons gain kinetic energy, etc.).

      In short:

      SR: high relative velocity -> length contraction
      GR: high acceleration and high momentum -> length contraction

      length contraction ~ time dilation (shorter trip, but also increases in frequencies of incoming particles and ensembles (i.e., incoming cold things are measured as hotter as you experience Lorentz contraction))

    40. Re:Damn it, now they tell me by Anonymous Coward · · Score: 0

      Bah, also there's a gravitational potential symmetry problem to be dealt with that makes ramjets (and possibly any sort of impulse-gain propulsion) much less efficient:

      As a classical object with a substantial rest-mass approaches c, the gravitational potential gradient around it sharpens, and the gravitational potential itself increases. As said in the previous post, this means things will blueshift substantially when falling in upon the the relativistic object. It also means things will redshift substantially on their way out symmetrically, so it will take ever more energy to accelerate any infallen/scooped-up protons to escape velocity.

      In the ultrarelativistic limit, the ship becomes a black hole with an escape velocity too high for any infalling protons to reach, so the ship begins to accrete, and in some frames of reference will become indistinguishable from a black hole.

      (In its own frame, it will drown in an increasingly dense and increasingly hot fog of infallen objects, unless the heater/reactor could produce exponentially increasing energy to the drawn-in protons).

      The other problem is that a relativistic qft treatment on an electromagnetic scoop would reveal propagation problems leading to a very small frontal surface from the perspective of the nonrelativistic interstellar medium. The ISM would certainly experience an enormous acceleration from the EM bow shock, but it would take exponentially stronger magnetic fields to actually draw the ISM matter into the heater/reactor. Moreover, as the self-gravitation of the ultrarelativistic ship increases, there will be greater distortions of the scoop, in that more and more of the geodesics available for excitations of the EM field can explore will lead back towards the ship itself.

      (At the same time, an increasing proportion of the geodesics that the exhaust particles can follow will also begin leading back towards the ship)

    41. Re:Damn it, now they tell me by RivenAleem · · Score: 1

      For relatively local trips,

      I c what you did there

    42. Re:Damn it, now they tell me by natehoy · · Score: 1

      This is an AMERICAN researcher. We routinely drive 5-mile trips at 80MPH in a 55MPH zone even though it will save, at most, less than a minute of actual drive time.

      --
      "This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
    43. Re:Damn it, now they tell me by Simetrical · · Score: 1

      Accelerating to 99.999998% of light speed in 3.5 hours would be a somewhat dizzying experience. Especially since you'd actually experience an acceleration equivalent to going to 5000 times light speed in a pure Newtonian universe. We're talking more than 500.000km/s^2 here -- or 50 million g.

      It wouldn't be dizzying if you could apply the appropriate force uniformly across all the particles in your body. If you were in a uniform gravitational field of 50 million g, you wouldn't even notice. At least, not as far as I can figure. We don't notice the force of gravity on Earth, we notice the normal force of the ground pushing up against our feet – if you jump down a long shaft in a vacuum, you'll feel weightless as you fall.

      Of course, we don't know of any way even in principle to create such a uniform force field other than actual gravity. But this is science fiction right now anyway, right?

      --
      MediaWiki developer, Total War Center sysadmin
  4. Do keep up, dear boy... by Space+cowboy · · Score: 4, Insightful

    After reading the article (yeah, I know...) tow thought spring to mind...

    1) Warp drive doesn't posit a traditional "go-very-fast-through-normal-space" type of spacecraft engine - it warps[*] space-time (hence the name!) in front of and behind the spacecraft - see here for an explanation. The spacecraft itself is sitting in a bubble of normal space, possibly even at rest.

    2) Um, ramjets, anyone ?

    Seriously, any number of sci-fi authors have covered this problem in enormous detail over the last few decades

    Simon

    [*] And because this is /., I expect you all to forgive me for using the present tense here [grin]

    --
    Physicists get Hadrons!
    1. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0, Funny

      [*] And because this is /., I expect you all to forgive me for using the present tense here [grin]

      Possibly. But it doesn't give you a free pass on spelling 'two' as 'tow' and not pluralizing thoughts in your opening sentence!

      MEIN FUHRER! I CAN EDIT!

    2. Re:Do keep up, dear boy... by jgtg32a · · Score: 4, Funny

      You did not just link me to a astrophysics article of wiki that's worse than tv tropes for me
       
      I'm at 8 articles from just the first link you provided.

    3. Re:Do keep up, dear boy... by Frosty+Piss · · Score: 0, Troll

      Seriously, any number of sci-fi authors have covered this problem in enormous detail over the last few decades

      Sci-Fi AUTHORS .

      --
      If you want news from today, you have to come back tomorrow.
    4. Re:Do keep up, dear boy... by NicknamesAreStupid · · Score: 1

      If this 'warp' were applied to one mass, hydrogen, then it should apply to anything in space -- nebulae, planets, suns, black holes. Most science fiction doesn't go that far. I suspect there are exceptions.

    5. Re:Do keep up, dear boy... by Ralph+Spoilsport · · Score: 1

      Yes, and if I have the magic ring I can disappear too!

      --
      Shoes for Industry. Shoes for the Dead.
    6. Re:Do keep up, dear boy... by inerlogic · · Score: 1

      yeh, you know, the guys who invented computers, robots, floppy disks, cell phone... etc....

    7. Re:Do keep up, dear boy... by confused+one · · Score: 4, Insightful

      Some of those authors have / had engineering and science degrees. That is part of what made them good at their job. Isaac Asimov and Arthur C. Clarke are classic examples.

    8. Re:Do keep up, dear boy... by Frosty+Piss · · Score: 0, Troll

      yeh, you know, the guys who invented computers, robots, floppy disks, cell phone... etc....

      No, no they didn't.

      --
      If you want news from today, you have to come back tomorrow.
    9. Re:Do keep up, dear boy... by Space+cowboy · · Score: 5, Informative

      Let me recap for you (both of the below points taken from the links I provided...):

      1) Proposed by the physicist Miguel Alcubierre, popularised by Star-Trek.

      2) Proposed by the physicist Robert W Bussard (hence "Bussard Ramjet"), popularised by Larry Niven (the author), and even referred to by Carl Sagan on TV and in books...

      Various other authors have used the same ideas. Perhaps I ought to have mentioned that I'm a physicist too... And the gentle humour regarding tense was supposed to clue you in that I wasn't suggesting we had a practical solution just yet... I wish I'd spelt "two thoughts" correctly, though.

      Simon

      --
      Physicists get Hadrons!
    10. Re:Do keep up, dear boy... by callmetheraven · · Score: 1

      The Pak Scouts ran one bussard ramjet in front of another, with the second burning the exhaust from the first as fuel! If you don't have a hyperdrive, all that hydrogen is a feature, not a bug.

      --
      You can have my SIG when you pry it from my cold, dead hands.
    11. Re:Do keep up, dear boy... by DerekLyons · · Score: 4, Insightful

      Seriously, any number of sci-fi authors have covered this problem in enormous detail over the last few decades

      Yes, any number of sci-fi authors have handwaved around these problems for the last few years. Actual scientists, not so much. And, as with TFA, the conclusions of the ones that have been less than sanguine. (From the POV of actually doing it.)

    12. Re:Do keep up, dear boy... by gestalt_n_pepper · · Score: 1

      When I was reading "Protector," I wondered why they didn't run them in series. Cumulative thrust would have put the ship closer to light speed.

      --
      Please do not read this sig. Thank you.
    13. Re:Do keep up, dear boy... by BubbaDave · · Score: 2, Interesting

      Perhaps not those specific things, but...

      http://www.technovelgy.com/

      "Explore the inventions and ideas of science fiction writers at Technovelgy (that's tech-novel-gee!) - over 1,865 are available. Use the Timeline of Science Fiction Invention or the alphabetic Glossary of Science Fiction Technology to see them all, look for the category that interests you, or browse by favorite author / book. Browse more than 2,770 Science Fiction in the News articles. "

      Dave

    14. Re:Do keep up, dear boy... by ArcherB · · Score: 1

      Seriously, any number of sci-fi authors have covered this problem in enormous detail over the last few decades

      I thought they changed their name to SyFi.

      --
      There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
    15. Re:Do keep up, dear boy... by ElectricTurtle · · Score: 2, Insightful

      IANAP, but I believe the idea is that empty space require less energy to 'warp', and that a few disparate atoms and molecules don't significantly change that energy requirement (which albeit is still huge). However, when you fill space with a lot of mass, and mass is energy, it presents a 'resistance' to warping that drives energy costs up to accomplish the goal. Such is my understanding of science-fiction FTL physics. ;-p

      --
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    16. Re:Do keep up, dear boy... by Graff · · Score: 1

      I thought they changed their name to SyFi.

      Even worse they went whole-hog and changed their name to SyFy!

    17. Re:Do keep up, dear boy... by IT+Slave · · Score: 1

      Actually folding of space is more likely to happen than anything else so there is not actual speed involved...Duh!!!!

    18. Re:Do keep up, dear boy... by Maximum+Prophet · · Score: 2, Interesting

      Seriously, any number of sci-fi authors have covered this problem in enormous detail over the last few decades

      Yes, any number of sci-fi authors have handwaved around these problems for the last few years. Actual scientists, not so much. And, as with TFA, the conclusions of the ones that have been less than sanguine. (From the POV of actually doing it.)

      Robert W. Bussard (August 11, 1928 – October 6, 2007) was an American physicist who worked primarily in nuclear fusion energy research. He was the recipient of the Schreiber-Spence Achievement Award for STAIF-2004.[1] He was also a fellow of the International Academy of Astronautics.

      See also, Bussard ramjet http://en.wikipedia.org/wiki/Bussard_ramjet

      Without a ramjet, you'd probably run out of fuel before reaching 99.999998 per cent of the speed of light.

      --
      All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
    19. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      While this is probably a joke... the evidence for a warp drive working is there, no single thing outlaws it.
      But building something capable of warping space time isn't something we know how to do, yet.
      Luckily, LHC might actually provide some insight in to this if we do discover the Higgs mechanism that gives everything mass. (artificial blackholes, here we come... kay maybe i shouldn't joke about this since LHC + blackholes = idiots screaming)

      We know high energy is capable of warping space, but i'm not sure we have ever been capable of performing it to the extent of say, being able to bend space enough to cause light to curve.
      Or have we? Please correct me if i am wrong.

    20. Re:Do keep up, dear boy... by jhutchins · · Score: 0, Flamebait

      Asimov's degree was honorary, for fund raising. He never worked as a scientist or engineer, he wrote.

    21. Re:Do keep up, dear boy... by Aerynvala · · Score: 1

      I thought they changed their name to SyFi.

      No, SyFy

      --
      http://transformativeworks.org/
    22. Re:Do keep up, dear boy... by Graff · · Score: 4, Interesting

      I wondered why they didn't run them in series. Cumulative thrust would have put the ship closer to light speed.

      Not necessarily. You are actually fusing those hydrogen atoms, turning them into helium. The output of one ramjet has less hydrogen than went into it. Yes, you could fuse that hydrogen/helium exhaust into heavier elements but it won't release as much energy. Basically you'll be adding mass to your spacecraft by putting another engine on but you won't be increasing your thrust as much as you may think.

      You might eke out a bit more acceleration with another engine in series but it's probably not worth it. You don't want to put them in parallel on a small ship either, for several reasons. For example, the magnetic fields that funnel material into the engine are supposed to extend in a cone far in front of the engine. Two engines that are close together will have their magnetic fields interact, complicating the management of those fields. Another concern would be properly adjusting those engines to maintain even thrust on both sides. When you're traveling at a significant fraction of the speed of light a slight variation in the hydrogen input of one engine could tear apart your spaceship pretty easily.

    23. Re:Do keep up, dear boy... by martas · · Score: 0, Offtopic

      pardon my ignorance, but is spelt really the past tense of spell?

    24. Re:Do keep up, dear boy... by DerekLyons · · Score: 4, Interesting

      And if you actually read the Wikipedia article you link to, rather than just drooling over the qualifications of the inventor, you'll find that as people have actually began to seriously study it - there are now significant doubts as to how well it will work. (Even assuming we figure out how to do the parts Bussard handwaved into existence, like the magnetic scoop.) In addition, even if it does work, it may be subject to the problems outlined in TFA.

    25. Re:Do keep up, dear boy... by camperdave · · Score: 0, Offtopic

      Personal Pet Peeve:
      Spelled - Constructed a word out of letters.
      Spelt - a type of grain.

      (Yes, I know spelled can be spelled "spelt", but it makes me cringe seeing it that way.)

      --
      When our name is on the back of your car, we're behind you all the way!
    26. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Asimov's degree was honorary, for fund raising. He never worked as a scientist or engineer, he wrote.

      His biochem degree appears to be earned - what degree are you referring to?

    27. Re:Do keep up, dear boy... by MozeeToby · · Score: 1

      The problem is that more recent work has found that Bussard Ramjets are probably impossible. No matter how you design the scoop you end up losing more energy dragging the atoms in than you can get out of fusing them. That said, I don't see those kinds of energies being a problem. A few yards of lead laced through with a coolant of some kind should do the trick if nothing else. If you're building a near lightspeed intersetellar spaceship, I would think that radiation shielding and cooling would be relatively low on your list of problems, even if it is at LHC energy levels.

    28. Re:Do keep up, dear boy... by fatmonkeyboy · · Score: 4, Informative

      You are completely and absolutely wrong. Are you getting him confused with someone else? Asimov studied for and received his Ph.D. in biochemistry the standard way. He then worked for the Navy during WWII as a chemist and was later a professor of biochemistry at Boston University. I know all of this because I was a huge fan as a kid (and read his autobiography multiple times). But here's the wikipedia article: http://en.wikipedia.org/wiki/Isaac_Asimov

    29. Re:Do keep up, dear boy... by thomst · · Score: 1

      Proposed by the physicist Robert W Bussard (hence "Bussard Ramjet"), popularised by Larry Niven

      ITIYM "Proposed by the physicist Robert W Bussard (hence "Bussard Ramjet"), popularised by Poul Anderson in his novel Tau Zero."

      Kids these days ...

      --
      Check out my novel.
    30. Re:Do keep up, dear boy... by LWATCDR · · Score: 1

      Yes it has been covered in many sci-fi stories because real physicist and scientists like yourself read those stories. The then write the author who as a who have a real love of science add them to future stores.

      As your spelling error I didn't notice. You see I unlike a lot of people have a high enough IQ that I can skill over and correct minor errors in spelling and grammar on the fly. It must be terrible to have such a limited IQ that such little errors cause people to miss the content of the message.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    31. Re:Do keep up, dear boy... by Lumpy · · Score: 2, Insightful

      You know until we fix the relativity thing, I think we need to just ignore all the other silly problems of near light travel.

      Hell that pesky E=Mc2 formula makes even getting to 1/2 the speed of light a massive pain in the ass.

      Scientific though experiments are fun and all, but I'd rather they figure out a propulsion system that can generate enough power to get a 1 person spacecraft hit 1/4 the speed of light without needing nearly the energy of an entire planet.

      "I'm on the return trip, let's suck up jupiter so we can make it home before supper."

      --
      Do not look at laser with remaining good eye.
    32. Re:Do keep up, dear boy... by paiute · · Score: 1

      Asimov's degree was honorary, for fund raising. He never worked as a scientist or engineer, he wrote.

      In the early 50's, Asimov was a biochemist on the faculty of the Boston University School of Medicine (which meant he was in the Department of Biochemistry), did research and taught biochemical graduate students, medical students, and dental students. In 1958 his writing income was way larger than his teaching salary, so BU let him stay on the faculty but write full time.

      --
      If Slashdot were chemistry it would look like this:Cadaverine
    33. Re:Do keep up, dear boy... by AlecC · · Score: 1

      Asimov's degree and Phd was fully earned. He then worked for a short while as an Associate Professor. When he left because writing was paying more, it was agreed that he could keep an honorary unpaid professorship. He was then awarded plenty of honorary doctorates for his writing,

      --
      Consciousness is an illusion caused by an excess of self consciousness.
    34. Re:Do keep up, dear boy... by LWATCDR · · Score: 1

      Well there is another reason. You can only take so many Gs. Odds are that only a small percentage of the hydrogen is being fused just as in a jet engine only a small amount of the o2 is burned. The rest you use as extra reaction mass.
      In theory you could fuse all the way to Iron with a net gain of power but each step gets you less and less and would probably add more and more mass to the ship for less gain. Of course all of this is "future tech" and outside the realm of anything but guessing.
      Of course you could just make a deal with the Outsiders and buy hyperdrive and be done with it.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    35. Re:Do keep up, dear boy... by gyrogeerloose · · Score: 1

      How about geosynchronous communications satellites, then? That innovation has been credited to Arthur C. Clarke.

      --
      This ain't rocket surgery.
    36. Re:Do keep up, dear boy... by CorporateSuit · · Score: 2, Funny

      We could just build the spaceships out of inside-out LHC tunnels!

      --
      I am the richest astronaut ever to win the superbowl.
    37. Re:Do keep up, dear boy... by LWATCDR · · Score: 1

      You do understand that besides a nuclear powered ion or plasma thruster system "and flight times of decades". All interstellar propulsion systems have a large amount of handwave produced parts and giant question marks?

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    38. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Simon says we have have faster-than-light space travel. Awesome!

    39. Re:Do keep up, dear boy... by Artifakt · · Score: 4, Informative

      Asimov worked specfically as a Munitions Chemist in WW2, alongside several other SF authors, including E. E. "Doc" Smith. Some of Isaac's war era work was classified well beyond that time (T.S. - 50 year to review at one time, according to Freedom of Information Act requests) and now seems to have become a matter of rumor and fallen from the official records, part of an interesting bunch of mostly unconfirmable claims suggesting that he, R A Heinlein, Jack Williamson, and maybe several other SF authors were consulted with regard to the Manhattan project just before Truman was informed. While that appears to be undocumented, There are Heinlein's own printed remarks about having two positions in the war, one of which he could talk about, and Larry Niven's comparison of what he and Jerry Pournelle did in advising the Bush administration after 9/11 to what a group of unspecified SF writers did in WW2, to make the rumors at least a trifle plausible.

      --
      Who is John Cabal?
    40. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Sure, just like Jon Stewart is an accurate, factual new reporter.

    41. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Yes; cf. knelt, slept, bent, wept, crept, lent, sent, learnt, e.g.

    42. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      My mother-in-law bends space enough to cause light to curve all the time. Posting as AC because her temper is even worse than her weight.

    43. Re:Do keep up, dear boy... by DerekLyons · · Score: 1

      You do understand that is exactly my point? Did you even bother to read what I wrote?

    44. Re:Do keep up, dear boy... by slashmojo · · Score: 1

      is spelt really the past tense of spell?

      Yes. At least in my oxford english dictionary..

      "spell (p.t. spelt)"

      Also on google dictionary..

      "* Spelt is a past tense and past participle form of spell. Britain"

      Maybe spelled is an american spelling?

    45. Re:Do keep up, dear boy... by SQLGuru · · Score: 1

      My Precious! Wants It! Give me Precious!

    46. Re:Do keep up, dear boy... by agw · · Score: 1

      1) Warp drive doesn't posit a traditional "go-very-fast-through-normal-space" type of spacecraft engine - it warps[*] space-time (hence the name!) in front of and behind the spacecraft - see here for an explanation. The spacecraft itself is sitting in a bubble of normal space, possibly even at rest.

      At least one Star Trek TNG book and a Stargate:Atlantis episode deal with that when the protagonists encounter near light speed vessels and have no means of just flying along side.

    47. Re:Do keep up, dear boy... by Maximum+Prophet · · Score: 1

      "Without a ramjet, you'd probably run out of fuel before reaching 99.999998 per cent of the speed of light."

      By the time you can reach the speeds where Interstellar dust and hydrogen are a problem, we'll have the tech to either deflect or scoop it. Right now, we can't do either, but it's not a problem because we can't go that fast.

      --
      All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
    48. Re:Do keep up, dear boy... by osu-neko · · Score: 1

      pardon my ignorance, but is spelt really the past tense of spell?

      Whether it's considered "standard" or not depends on which country you're in, but yes.

      --
      "Convictions are more dangerous enemies of truth than lies."
    49. Re:Do keep up, dear boy... by osu-neko · · Score: 3, Funny

      (Yes, I know spelled can be spelled "spelt", but it makes me cringe seeing it that way.)

      Your country of origin colours your perception of spelling.

      --
      "Convictions are more dangerous enemies of truth than lies."
    50. Re:Do keep up, dear boy... by osu-neko · · Score: 1

      Yes, you could fuse that hydrogen/helium exhaust into heavier elements but it won't release as much energy. Basically you'll be adding mass to your spacecraft by putting another engine on but you won't be increasing your thrust as much as you may think.

      Perhaps not, depending on what you thought, but it does avoid the problems of trying to run them in parallel, and the fact that the second engine doesn't need a ramscoop may make it's mass negligible compared to the first. Without knowing the engineering specifics, it's impossible to calculate, but it's certainly possible it would be a speed and efficiency win rather than a loss.

      --
      "Convictions are more dangerous enemies of truth than lies."
    51. Re:Do keep up, dear boy... by chromas · · Score: 1

      I cringt as well.

    52. Re:Do keep up, dear boy... by shadowfaxcrx · · Score: 1

      Warp drive doesn't posit a traditional "go-very-fast-through-normal-space" type of spacecraft engine - it warps[*] space-time (hence the name!) in front of and behind the spacecraft - see here for an explanation. The spacecraft itself is sitting in a bubble of normal space, possibly even at rest.

      Yes, but the current school of thought is that it would not be a violation of the laws of physics to do this, but even assuming we invented the technology that was capable of it, it would require so much energy as to make it completely unworkable. That alliance with the Klingons isn't going to last very long if we have to extract all the energy on their planet to get back home after a diplomatic mission ;)

      That said, I'm sure that eventually (barring our extinction) we will figure out how to travel faster than light speed.

      Remember, before Bell Aircraft came along and just did it, scientists opined that breaking the sound barrier was impossible too.

      If we went back to the dark ages and told them about cars, and GPS navigation, and fighter planes, they'd say it was impossible, just as we are now saying that FTL travel is impossible.

      --
      "I disagree with you" does not equal "flamebait."
    53. Re:Do keep up, dear boy... by martas · · Score: 1

      well, i've always spelled the past of spell as spelled, and never got into any trouble for it...

    54. Re:Do keep up, dear boy... by Daniel+Dvorkin · · Score: 2, Informative

      Remember, before Bell Aircraft came along and just did it, scientists opined that breaking the sound barrier was impossible too.

      No they didn't. It was understood since the nineteenth century that the "sound barrier" was an engineering problem, not a scientific one.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
    55. Re:Do keep up, dear boy... by Destoo · · Score: 1

      I think that word just made me throw up in my mouth a little.
      Where's my "-1, Yuck" mod.

      --
      Nouvelles de jeux et technologies en français. TC
    56. Re:Do keep up, dear boy... by HiThere · · Score: 1

      Don't you need to be sponsored by the Puppeteers before they'll even deign to talk to you?

      Well, unless you develop your own starseed lure.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
    57. Re:Do keep up, dear boy... by Sethumme · · Score: 1

      I LOLt.

    58. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Personal pet peeve:
      Tunnel vision with dictionaries.

      Spelt (v): pt. and pp. of SPELL
      Spelt (n): variety of wheat

      It requires a special kind of selective reading to ignore applicable definitions while on a quest to "correct" someone. A word cannot be confined exclusively to a single definition when there are many that may apply.

      Yet you people do it all the time, in all kinds of discussions. Most egregious violation: whining about the definition of the verb "steal".

    59. Re:Do keep up, dear boy... by BubbaDave · · Score: 1

      Yeah, crappy name, but interesting material.

      Dave

    60. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Yeah, why can't people actually visualize this is relatively simple terms?
      You have what essentially is a big funnel. If you increase the amount going into the funnel eventually you will overload it's output capacity. With a fixed size funnel you are limited by volumetric efficiency.

    61. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Since we're playing that game: you don't get a pass for not putting "thoughts" in quotation maks. Unless you think it really is possible to pluralize a thought in a sentence...

      HA!

    62. Re:Do keep up, dear boy... by ceoyoyo · · Score: 2, Insightful

      Personal Pet Peeve:

      Americans who butcher the queen's english and then cringe when they hear/see it spoken/written correctly.

    63. Re:Do keep up, dear boy... by Graff · · Score: 1

      Without knowing the engineering specifics, it's impossible to calculate, but it's certainly possible it would be a speed and efficiency win rather than a loss.

      Yeah, that's really my point. It's not a definite win so it's not definitely something that the characters in that universe should have done. Add to that the fact that the ramjets were in short supply (they were taken from the wall of the ring and there were only so many of them) and were being used for multiple spacecraft, it might just not have been viable.

    64. Re:Do keep up, dear boy... by Marxist+Hacker+42 · · Score: 1

      Not only that- but his Doctorate Committee were apparently huge fans of his work- he got a joke question on a minor short story that he wrote to practice the turgid writing style that was popular for research papers at the time, on the chronotic effects of an entirely made up chemical that supposedly dissolved in water pre-emptively.

      --
      SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
    65. Re:Do keep up, dear boy... by qsliver · · Score: 1

      Your country of origin colours your perception of spelling.

      Fortunately many of us still honour the original flavour of the mother tongue. (Or should that be "mothour"?)

      --
      The above comments are the ravings of a lunatic and should be ignored completely.
    66. Re:Do keep up, dear boy... by drinkypoo · · Score: 1

      As your spelling error I didn't notice. You see I unlike a lot of people have a high enough IQ that I can skill over and correct minor errors in spelling and grammar on the fly.

      Unfortunately, it is not high enough to know that your condescending comment will only make you look like a jackass. That, or IQ doesn't actually correlate to anything worthy of being called "intelligence".

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    67. Re:Do keep up, dear boy... by DrCode · · Score: 1

      Okay, so it's a solved problem. Now all we have to do is find a source of dilithium and we're good to go!:-)

    68. Re:Do keep up, dear boy... by mOdQuArK! · · Score: 1

      I wonder how long it would take to reach 25% of c by repeatedly slingshotting a large multi-generation colony ship around the Sun...

    69. Re:Do keep up, dear boy... by Clovert+Agent · · Score: 1

      Alastair Reynolds is a very good sci-fi author and a qualified astronomer. He dealt with the question of near-light speed and FTL travel in various ways in various books.

      Worth a read, and hopefully after that you'd be a bit less keen to dismiss the entire community of sci-fi authors as clueless amateurs. There are some very good "hard" SF writers. Their science is still fiction, but at least it makes an effort to remain grounded in what today's science can offer or predict.

    70. Re:Do keep up, dear boy... by DerekLyons · · Score: 1

      What makes you think I don't read sci-fi?

    71. Re:Do keep up, dear boy... by tehcyder · · Score: 1

      No, in the UK, it's always written "spelled" never "spelt". Although it's actually pronounced "spelt", but that's another issue.
      I'm afraid I might be loosing some of the Americans here...

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    72. Re:Do keep up, dear boy... by Anonymous Coward · · Score: 0

      Of course (s)he didn't. With such a low uid one doesn't have to.

    73. Re:Do keep up, dear boy... by NotBornYesterday · · Score: 1

      Spelt (Triticum spelta) is an ancient form of grain related to wheat.

      If I were less pedantic, I might note that American english generally goes with "spelled", while I have heard that UK/Aussie writing often uses "spelt".

      --
      I prefer rogues to imbeciles because they sometimes take a rest.
    74. Re:Do keep up, dear boy... by bar-agent · · Score: 1

      I wonder how long it would take to reach 25% of c by repeatedly slingshotting a large multi-generation colony ship around the Sun...

      A slingshot around the Sun would not in itself change your velocity relative to the Sun. If you do a powered slingshot, it would give you more bang for your thruster buck, so you would reach 25% of c in less time, depending on how much thrust you can manage. But the escape velocity of the Sun is only .2% of c, so I would not expect much help.

      --
      i'd hit it so hard, if you pulled me out you'd be the king of britain [bash.org]
    75. Re:Do keep up, dear boy... by mOdQuArK! · · Score: 1

      Yeah, after posting my comment, I thought about it a little more & realized that you wouldn't be able to pick up any more momentum via gravity slingshot after reaching the escape velocity, but I didn't know what the exact escape velocity from the Solar System was.

  5. so if I stand in front of the beam... by Anonymous Coward · · Score: 1, Funny

    I go back into the past ?

    1. Re:so if I stand in front of the beam... by Anonymous Coward · · Score: 0

      Exactly; then you will change the space time continuum so you would blink out of existence.

  6. Let's just hope... by Hognoxious · · Score: 4, Funny

    Let's just hope the engine controls aren't made by Toyota, or it'll be hitting that speed whether the crew want or not.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    1. Re:Let's just hope... by Anonymous Coward · · Score: 0

      The faulty parts were actually made in America, to sabotage Toyota and start a FUD campaign to encourage Americans to become afraid of foreign cars and buy GM's pieces of shit. But what about the Woz' criticism of his Prius?

      The answer to that question is that the Woz is a bearish girly-man who dosen't know how to drive. If he can't even handle a Prius, he'd probably kill himself driving a Corolla or Town Car.

    2. Re:Let's just hope... by Anonymous Coward · · Score: 0

      They're facing more than one recall right now, for things other than some gas pedal assemblies made in the U.S.

      And beyond that - those gas pedal assemblies obviously passed any quality assurance that Toyota had in place. It's their job to make sure that the parts they are buying are up to the specifications. They failed to do that.

      FUD campaign? Take off the tinfoil hat and get back to me.

    3. Re:Let's just hope... by SleeknStealthy · · Score: 2, Insightful

      I am afraid toyota's quality problems far exceed simple material issues PPS / PA46 caused by a friction lever or faulty floor mats. Toyota stopped testing their cars properly prior to launch and relied on everyone else to be their test dummies. This is gross negligence on the part of any manufacturer and now they are only beginning to pay the price. I think everyone should be scared when they press on a brake and it takes a second to begin slowing the car down. You would think when you design a car the braking system would have a pretty high priority when testing. I mean if a car company gets one piece of equipment right, it should be the one to stop the 1 ton+ bullet flying out of control. I am just waiting for all the software bugs in the ECU to come out.

      --
      Math
    4. Re:Let's just hope... by Bakkster · · Score: 1, Troll

      The faulty parts were actually made in America, to sabotage Toyota and start a FUD campaign to encourage Americans to become afraid of foreign cars and buy GM's pieces of shit.

      Toyota makes remarkable demands of several domestic (US) auto-parts manufacturers, requiring incredible engineering investment.

      Then they order the minimum quantity, sending them to China to be reverse engineered and mass-produced. Goodbye margins!

      --
      Write your representatives! Repeal the 2nd Law of Thermodynamics!
    5. Re:Let's just hope... by Lumpy · · Score: 2, Informative

      we can also ignore the fact that the Parts worked perfectly, it's the SOFTWARE that was screwed up. That was made by Toyota, tested by toyota, and Approved by toyota.

      As to the GP, GM "pieces of shit' are mostly china parts assembled in mexico or Canada. You cant buy an American car anymore. They dont exist.

      --
      Do not look at laser with remaining good eye.
    6. Re:Let's just hope... by liquiddark · · Score: 1

      Interesting, then, that the engineers I know at the company were panicking when the Big Three threatened to collapse, since it would wipe out most of the major parts suppliers on the continent and thus destroy Toyota's ability to get reasonably-priced parts supply for North American plants.

    7. Re:Let's just hope... by Sponge+Bath · · Score: 1

      Your claim does not match what is being reported. Toyota continues to work with CTS, the American parts company making the accelerator assemblies in question, to improve the product and build more.

      Even if your claims are correct, then Toyota met all of its contractual requirements, provided income to American companies and seeks to reduce costs. That does not sound evil to me.

    8. Re:Let's just hope... by name_already_taken · · Score: 1

      The faulty parts were actually made in America, ...blah blah blah nonsense

      Actually, there were reports of unintended acceleration in Toyota cars built before Toyota started using American made throttle pedal assemblies.

      The problem lies with the Toyota pedal design (designed by Toyota, I might add), or Toyota's engine control system, also designed by Toyota.

      --
      Putting moderation advice in your .sig lowers your karma!
    9. Re:Let's just hope... by Bakkster · · Score: 1

      Even if your claims are correct, then Toyota met all of its contractual requirements, provided income to American companies and seeks to reduce costs. That does not sound evil to me.

      You can still be evil while following the letter of the contract (in geeky terms, lawful evil).

      Minimum orders were based on covering the design cost with the overhead, anticipating additional orders to make profit. Toyota in-turn steals their intellectual property (the real kind of intellectual property, we're not talking digital bits). They could turn Toyota down, but without their business there would be even more layoffs. So income was provided to American employees, not their companies. Of course, this company has gone through several rounds of layoffs already, overtime is mandatory and unpaid, and benefits are unheard of in an attempt to keep their heads above water.

      I'm not certain that Toyota's other suppliers get the same raw deal. However, I have several buddies who work for this supplier and have confirmed this fact to me. And yes, they supply highly engineered components that are crucial to auto performance, not just cupholders or molding.

      --
      Write your representatives! Repeal the 2nd Law of Thermodynamics!
    10. Re:Let's just hope... by osu-neko · · Score: 1

      Indeed. Cars are made on Earth. Trying to get more specific than that is delusion, i.e. marketing.

      --
      "Convictions are more dangerous enemies of truth than lies."
    11. Re:Let's just hope... by Clandestine_Blaze · · Score: 1

      As to the GP, GM "pieces of shit' are mostly china parts assembled in mexico or Canada. You cant buy an American car anymore. They dont exist.

      Sure you can! The Toyota Camry made the Cars.com American-Made Index top choice in terms of domestic parts used and factories in which it was assembled.

      Okay, so Toyota isn't an American company, I get your point there, but they are still have to pay taxes here and are traded on the NYSE, so any investor can invest in the profits.

    12. Re:Let's just hope... by Grishnakh · · Score: 1

      Sorry if I'm asking in the wrong place, but what's the deal with this delayed brake pedal thing anyway? Do Priuses not have regular hydraulic brakes? I understand they have regenerative braking (done with the motor), but wouldn't it be easy to implement that by having the first amount of brake pedal travel activate the regen braking, and then after you've pressed a certain amount, the hydraulic brakes start working? This is just like my hydraulic clutch pedal, which has an adjustable free-play portion: you have to press it in a certain amount (not much) before the piston starts placing pressure on the hydraulic fluid. Didn't Toyota just implement their brake pedal this way, putting the regen brakes in that first amount of travel? Or did they really make it so that there's software between your brake pedal and the hydraulics, which is a horrible idea if you ask me?

    13. Re:Let's just hope... by Grishnakh · · Score: 1

      The other problem, as I understand it, is a complete lack of an "OFF" button. Instead, they have a stupid "engine start" button which you have to hold down for 3 seconds to turn off the engine. That's an insanely idiotic idea; if your car is accelerating out of control, 3 seconds is way too long to wait with your finger on a button while you try to steer around pedestrians and traffic.

      Also, unless I'm mistaken, for some reason these things will not allow you to shift into neutral when this happens.

    14. Re:Let's just hope... by Anonymous Coward · · Score: 0

      none of those cars have 100% american made components, american designed, american built.

      Even the Tesla is not american made. it's a Lotus Eliese with a different drivetrain

    15. Re:Let's just hope... by Anonymous Coward · · Score: 0

      but wouldn't it be easy to implement that by having the first amount of brake pedal travel activate the regen braking, and then after you've pressed a certain amount, the hydraulic brakes start working?

      As I've always understood it, thats exactly how they've always had the Prius brakes; the problem is that the software is incapable of handling all braking scenarios, it would seem. If you brake while going over a bump, a pothole, or any other less-than-perfect bit of road surface; the power to the wheels is cut; and the braking is cut; this only happens for about a half a second, but if you are not used to the behavior, it is VERY scary. I have had several near-collisions because of it. If it was a faulty physical part, that would be one thing, but it seems they just have shit software, which, considering all the tech that is in the Prius, is pretty shameful.

    16. Re:Let's just hope... by Grishnakh · · Score: 1

      So are you saying that the software acts weird in certain scenarios for the regenerative portion, and that's causing people to have wrecks, but the hydraulic brakes are still there, if the drivers would simply press the brake pedal in more?

      It sounds like a lot of the problem is trying to make things too transparent to the user, instead of having users that intimately understand how the car works. This is exactly why pilots are trained to know a decent amount about how their machines work, so that they understand what's happening when something goes wrong, and they know how to correct it (or what not to do because it'll make it worse). Maybe we should start training car drivers this way, and only license them to drive certain makes and models of cars.

  7. Pffft... by Manhigh · · Score: 1

    Just engage the Edelstein compensators.

    Come to think of it, this professor is probably hoping to have some scifi tech named for him.

    --
    "Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
    1. Re:Pffft... by jgtg32a · · Score: 1

      I thought that they just called it navigation shielding, originally they just talked about it to protect against asteroids, but looks like they would be far more useful against hydrogen.

    2. Re:Pffft... by Lumpy · · Score: 1

      at those speeds, hydrogen buildup is the least of your worries. One speck of sand will rip through all your shielding, the hull, all the contents, and blow out the rear of the craft and still sit there going "huh? What was that?" It's why one of the most realistic space weapons would be a sandcaster. Simply get in the path of your target and shoot out sand. They will not be able to detect it, AND it will shred even a ship with 100mm thick titanium hulls.

      --
      Do not look at laser with remaining good eye.
    3. Re:Pffft... by osu-neko · · Score: 1

      Nice idea, but poor name. Call it an "Instant Micro-Asteroid Field Generator" and you'll be able to sell them much more readily than calling it a "sandcaster". Unfortunately, military clients will begin referring to it by its initials...

      --
      "Convictions are more dangerous enemies of truth than lies."
  8. simple solution: by notgm · · Score: 5, Funny

    put a hydrogen-atom-splitter on the bow of the ship, they'll just get cut in half and fall out of the way.

    1. Re:simple solution: by ionix5891 · · Score: 1

      dont forget to reverse the polarity of the bow deflector

    2. Re:simple solution: by jbeaupre · · Score: 5, Funny

      You joke, but that might be an actual solution. If you can go that fast, why not postulate some other technology. Something that causes hydrogen to have a 50% probability of being on the left, 50% on the right. Just for a microsecond. Let it collapse back to the middle once you've gone past.

      Really you'd want to create some sort of probability donut. Fly right through the middle. I propose calling it the Homer-Schrodinger shield.

      --
      The world is made by those who show up for the job.
    3. Re:simple solution: by Mr+Z · · Score: 4, Funny

      Hmmm.... something tells me that cutting a large number of single protons in half right in front of the ship would more than double their problems....

    4. Re:simple solution: by Graff · · Score: 1

      something tells me that cutting a large number of single protons in half right in front of the ship would more than double their problems....

      No no, they aren't splitting protons - they are splitting atoms! As in, all the electrons go to the left and all the protons go to the right!

    5. Re:simple solution: by kpainter · · Score: 1

      Really you'd want to create some sort of probability donut. Fly right through the middle. I propose calling it the Homer-Schrodinger shield.

      I think it should be called the Siegfried-Roy donut puncher effect.

    6. Re:simple solution: by Anonymous Coward · · Score: 0

      Hmmmmm... Homer-schrodinger shield.

      MArge!

    7. Re:simple solution: by Mashdar · · Score: 1

      It is called a 2D plane bisecting a 3D space. Now we just have to fit the ship on it.

    8. Re:simple solution: by Mashdar · · Score: 1

      We will just have to convert them to 2H, then!

    9. Re:simple solution: by Mr+Z · · Score: 1

      That's not what's usually understood when someone says they're splitting atoms. Otherwise, I could split a few million just scuffing my socks on the carpet or by forgetting to put a dryer sheet in when I do laundry.

      Besides, there's an awful lot of ionized hydrogen out there. (Basically, just protons floating around, possibly with a neutron attached).

      In any case, protons are a few orders of magnitude more massive than electrons. You're gonna need a strong-ass rudder to keep from going in circles!

    10. Re:simple solution: by ca111a · · Score: 1

      improbability donut - here, corrected that for ya :)

    11. Re:simple solution: by elfprince13 · · Score: 1

      I think douglas adams had something to say on that subject.

    12. Re:simple solution: by Anonymous Coward · · Score: 0

      Mmmmmm....probability donuts!

    13. Re:simple solution: by xOneca · · Score: 1

      Why not simply push them away?

    14. Re:simple solution: by RealErmine · · Score: 1

      put a hydrogen-atom-splitter on the bow of the ship, they'll just get cut in half and fall out of the way.

      You don't have to split them. Think Space Cow-Catcher. (Space-Cow Catcher?)

      --
      Dewey, you fool! Your decimal system has played right into my hands!
    15. Re:simple solution: by Graff · · Score: 1

      That's not what's usually understood when someone says they're splitting atoms. Otherwise, I could split a few million just scuffing my socks on the carpet or by forgetting to put a dryer sheet in when I do laundry.

      Lol, yeah, it was just a joke.

      Technically though, splitting an atom usually means you take all the protons and neutrons in the nucleus and split them into two or more groups of protons and neutrons without changing the total amount of them. You really can't split a hydrogen atom because it only has 1 proton and no neutrons. I suppose if it was deuterium or tritium you could split it.

    16. Re:simple solution: by Mr+Z · · Score: 1

      Yeah, about the only way you could would be to break the proton into quarks and such, much like the LHC would. Hence my original comment. :-)

    17. Re:simple solution: by crtreece · · Score: 1

      If we're speculating, let's make a device that generates an infinite field of improbability. You could then occupy every point in the universes simultaneously. You would then collapse the improbability field to arrive at a specific point.

      --
      file: .signature not found
  9. LHC by mcgrew · · Score: 3, Funny

    "hydrogen atoms would seem to reach a staggering 7 teraelectron volts," which for the crew "would be like standing in front of the Large Hadron Collider beam."

    Wow, free energy!

    1. Re:LHC by Anonymous Coward · · Score: 0

      And just accelerate a bit more and it'll create a black hole to warp into another universe!
      That's really Interesting! :)

    2. Re:LHC by blueg3 · · Score: 1

      Free momentum going in the wrong direction!

    3. Re:LHC by RivenAleem · · Score: 1

      I propose baguette-shaped ships

  10. Well... by Anonymous Coward · · Score: 0

    That is why there is a main deflector, you idiot.

  11. Oh noes by gparent · · Score: 3, Funny

    Guess we'll just have to go at 99.999997% of the speed of light then.

    1. Re:Oh noes by Anonymous Coward · · Score: 0

      ... or 100.000001%, at which point ... well, to be quite honest I have no idea what the hell happens but I suspect the rules change.

    2. Re:Oh noes by mcgrew · · Score: 1

      That's pretty damned slow when it comes to interstellar travel. Alpha Centauri (or is it Proxima?) would take a four year journey one way, and that's the second closest star to the earth.

    3. Re:Oh noes by MightyMartian · · Score: 1

      You can't accelerate to light speed. In fact, the energy requirements of accelerating anything to within a few hairs of the speed of light would have insanely huge energy requirements. I'd say if we could get a manned spacecraft to go 5% to 10% the speed of light, we'd probably be doing pretty good, and must have some pretty awesome source of energy.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    4. Re:Oh noes by Anonymous Coward · · Score: 0

      It would only take four years to outside observers. The ship's occupants would experience less time since they're travelling so fast.

    5. Re:Oh noes by Mad-Bassist · · Score: 1

      Nah, it's just slow to everyone else in the universe. Special Relativity is on the side of the fast traveler.

      --
      "The only legitimate use of a computer is to play games." - Eugene Jarvis
    6. Re:Oh noes by NatasRevol · · Score: 4, Informative

      10% of the speed of light is 67 million miles per hour.

      Helios 2 - fastest manmade object ever - went about 150,000 mph.
      http://www.aerospaceweb.org/question/performance/q0023.shtml

      So, yeah even 1% of the speed of light would be 40x faster than anything else we've ever done.

      --
      There are two types of people in the world: Those who crave closure
    7. Re:Oh noes by Anonymous Coward · · Score: 0

      That's pretty damned slow when it comes to interstellar travel. Alpha Centauri (or is it Proxima?) would take a four year journey one way, and that's the second closest star to the earth.

      No. It won't. That is a very common error with relativity.

      For an observer on Earth, it will always take four years or more for anything to reach a place four light years away. But for the traveler, that sees the space contracting around him/her, it would take 8 1/2 hours to reach that distance at 0.99999997c.

    8. Re:Oh noes by CharlyFoxtrot · · Score: 1

      That's pretty damned slow when it comes to interstellar travel. Alpha Centauri (or is it Proxima?) would take a four year journey one way, and that's the second closest star to the earth.

      Four years isn't that long, the voyages of the great seafaring explorers of old took that long too. Of course they could stop along the way but I think that if people can survive 20 years locked up in a prison cell they can probably handle a 10 year round trip.

      --
      If all else fails, immortality can always be assured by spectacular error.
    9. Re:Oh noes by sleigher · · Score: 1

      You mean something like 7 teraelectron volts. Maybe that woul do it no?

      --
      All points of time and space are connected.
    10. Re:Oh noes by Anonymous Coward · · Score: 0

      Except that I think you forget time dilation. I think were you to undertake the journey, you'd find it didn't take you very long to get there at all. On the other hand, I'd probably think it took you four years.

    11. Re:Oh noes by maxwell+demon · · Score: 2, Insightful

      Don't forget you have to accelerate and decelerate. At an acceleration which you can survive.

      --
      The Tao of math: The numbers you can count are not the real numbers.
    12. Re:Oh noes by blueg3 · · Score: 3, Informative

      For large objects, that is. We regularly accelerate small particles to large fractions of lightspeed.

    13. Re:Oh noes by MightyMartian · · Score: 1

      So one has to accelerate to over 99% the speed of light so they can gain the energy to accelerate to 10%? I may not be a physicist, or even a math professor, but methinks there are serious problems with your logic.

      If we're going to accelerate something as big as a ship to even 1/50th the speed of light, we're going to need a way of producing a lot of energy to move that object from an effective rest mass. Problems like hydrogen atoms basically roasting everyone inside the ship hardly seems an issue.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    14. Re:Oh noes by zzsmirkzz · · Score: 1

      You can't accelerate to light speed. In fact, the energy requirements of accelerating anything to within a few hairs of the speed of light would have insanely huge energy requirements.

      Yet, light itself has the necessary energy to do this with no problems, and can travel at that speed over a seemingly infinite distance. It seems to me that some people have a very inaccurate view of the available, untapped, energy all around them, in every atom of everything, everywhere. It might even say the energy supply is unlimited....

    15. Re:Oh noes by Anonymous Coward · · Score: 0

      So, yeah even 1% of the speed of light would be 40x faster than anything else we've ever done.

      As long as the pizza is hot & fresh when it shows up at my door.

    16. Re:Oh noes by mcgrew · · Score: 1

      Yeah, and that's only ONE star (ok, two since it's a binary system). You're still not getting very far. There are only 100 stars within 20 light years from earth, among the billions in the galaxy.

      Of course they could stop along the way but I think that if people can survive 20 years locked up in a prison cell they can probably handle a 10 year round trip.

      What are you going to do, sentence criminals to a round trip to Alpha Centauri?

    17. Re:Oh noes by sleigher · · Score: 1

      I am neither a physicist nor a math professor either, but I do find articles about why we cannot travel the speed of light fun to read. As far as logic goes, I find it illogical to think that those of us alive today will travel anywhere near the speed of light. 7 teraelectron volts was my poor attempt at humor...

      --
      All points of time and space are connected.
    18. Re:Oh noes by mcgrew · · Score: 1

      Yes, but when you get back at least eight years will have passed, even if it only seems like six months to you. Rip Van Winkle syndrome?

    19. Re:Oh noes by MightyMartian · · Score: 1

      Photons are massless, therefore do not suffer the problem that an object with mass does; namely that the closer to c an object approaches, the greater the mass it has, and an object would have infinite mass at c, thus requiring infinite energy to accelerate to c. Since photons are massless, they do not suffer the impossible situation of requiring an infinite amount of energy to move at the speed of light. As well, photons always travel at c, though matter can modify momentum and wavelength.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    20. Re:Oh noes by Anonymous Coward · · Score: 0

      Um, I just turned on my flash light. Pretty sure the beam it the wall at the speed of light
      .

    21. Re:Oh noes by zzsmirkzz · · Score: 1

      Maybe I should learn more about physics, but are you saying that objects gain mass as their velocity increases? I understand that they gain momentum as well as potential energy, but I have never heard that they gain mass.

    22. Re:Oh noes by MightyMartian · · Score: 1

      The mass of an object approaches infinity as it approaches the speed of light. At the speed of light, an object's mass would be infinite, and the energy required to get it there would also be infinite. This is why the speed of light is the barrier that it is.

      http://galileoandeinstein.physics.virginia.edu/lectures/mass_increase.html

      In particular, this passage:

      Einstein was so sure that momentum conservation must always hold that he rescued it with a bold hypothesis: the mass of an object must depend on its speed! In fact, the mass must increase with speed in just such a way as to cancel out the lower y-direction velocity resulting from time dilation. That is to say, if an object at rest has a mass M, moving at a speed v it will have a mass . Note that this is an undetectably small effect at ordinary speeds, but as an object approaches the speed of light, the mass increases without limit!

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    23. Re:Oh noes by tftp · · Score: 1

      Alpha Centauri (or is it Proxima?) would take a four year journey one way, and that's the second closest star to the earth.

      I guess we'll all have to go. Then there will be no exernal observer left, and our own time will dilate to some ridiculous 7 minutes. So I'm claiming copyright on the name "Spaceship Earth."

    24. Re:Oh noes by Grishnakh · · Score: 1

      But 1% is still far too slow to be sufficient for interplanetary travel of any kind. Even with automated probes, it'd take well over 400 years to get to Alpha Centauri, our nearest neighbor, and transmit any useful data back. By that time, we'll probably have developed faster propulsion systems.

    25. Re:Oh noes by amorsen · · Score: 1

      True, but do YOU want to ride the LHC?

      --
      Finally! A year of moderation! Ready for 2019?
    26. Re:Oh noes by mcgrew · · Score: 1

      So I'm claiming copyright on the name "Spaceship Earth."

      I think you're a little late; there was a book by that name. At any rate, you can't copyright a two word phrase, but you could trademark it... if someone hasn't done so already.

    27. Re:Oh noes by element-o.p. · · Score: 1

      Except when you spend ten years in a prison cell*, you don't have to bring your own oxygen, water, food, etc.

      * At least not in the U.S**. If you go to prison in other countries, YMMV.

      ** Offer void in Guantanamo Bay.

      --
      MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
    28. Re:Oh noes by Anonymous Coward · · Score: 0

      >implying LHC works

    29. Re:Oh noes by Tempest451 · · Score: 1

      "but as an object approaches the speed of light, the mass increases without limit!" See! It's this last part that I always have a problem with. Mathematicians don't like equations that result in infinities for a reason, it means their math is wrong some where. Now if it is a "perceived" infinity there is some room for interpretation. I ask, is their a such thing as infinitely small, infinitely large? I think either there needs further experimentation or better wording.

    30. Re:Oh noes by dylan_- · · Score: 1

      hat's pretty damned slow when it comes to interstellar travel. Alpha Centauri (or is it Proxima?) would take a four year journey one way

      That's Earth time. Onboard travel time would be about 9.5 hours, which isn't too bad.

      --
      Igor Presnyakov stole my hat
    31. Re:Oh noes by qbast · · Score: 1

      Why not? Worked great in Australia.

    32. Re:Oh noes by tehcyder · · Score: 1

      What are you going to do, sentence criminals to a round trip to Alpha Centauri?

      Why not? If you could cut your jail time from say 20 years down (Earth time) to 1 year (perceived time) I imagine a lot of people would jump at the chance - although there would no doubt be complaints about going soft on criminals.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    33. Re:Oh noes by mcgrew · · Score: 1

      And when you get home, ten years have passed, the technology has changed, everyone you knew is ten years older and have forgotten all about you. Your ten year old son is grown, your wife has divorced you, and you can no longer fit into society.

    34. Re:Oh noes by MightyMartian · · Score: 1

      I'm no physicist, nor am I a mathematician. But a century of research into Relativity does not indicate that this is flawed math, but rather that accelerating anything with mass to the speed of light is simply impossible. By the interpretations I see, accelerating anything, with or without mass, is impossible. Particles that travel at the speed of light pretty much are created at that speed, they don't ramp up. Even theoretical particles like tachyons, which could travel faster than the speed of light, do not accelerate to that.

      Sometimes an impossible answer simply indicates that something is impossible. I don't think there's been a physicist in the better part of a century that thought folks were just misinterpreting Einstein.

      --
      The world's burning. Moped Jesus spotted on I50. Details at 11.
    35. Re:Oh noes by dylan_- · · Score: 1

      What a depressing view of things. I'd like to take a time trip like that, spend a couple of weeks away and come back to see what Earth was like 10 years later. I'd take my wife and child with me of course or, more likely, wouldn't travel if I had a child.

      As for fitting into society, I managed it in 1999, I'm sure I can manage in 2019. ;-

      --
      Igor Presnyakov stole my hat
    36. Re:Oh noes by bingoUV · · Score: 1

      The equations result in divide-by-zero when speed is c (speed of light in vacuum). This does not mean that the values are infinite at speed c. This just means that the value is undefined.

      Though as far as limit is concerned, yes the values do approach infinite. That is to say, as far as speed is less than c, increases in speed results in increase in the value (whether it be mass, momentum etc.) without limit. But when the speed becomes c, these equations fail to give a proper answer.

      You are right in saying that equations failing to give a proper answer could mean the situation is impossible. But, then, maybe some other laws take over once the speed of c is somehow attained.

      --
      Bingo Dictionary - Pragmatist, n. A myopic idealist.
  12. Clearly by Hell+O'World · · Score: 1

    If you want to travel light speeds, you have to convert yourself into light first.

  13. Yes, ONLY interstellar hydrogen... by Anonymous Coward · · Score: 0

    Curses! We were almost there!

  14. So what by Anonymous Coward · · Score: 0

    By that time we'll have our deflection shield up. The hydrogen would simple flow around the bubble as it will not see the hole in space/time we will be creating to travel that fast. The other option is to simply not go that fast but faster leaving the hydrogen in our dust. Est that suck'azzz.

  15. Considering the energy required. . . by Salgak1 · · Score: 5, Insightful

    . . .to GET to .99999998 c, this is unlikely to be a concern. And if you have the effectively-infinite energy to move a ship at this speed, providing sufficient shielding should be a trivial exercise in additional hand-wavium. . . .

    1. Re:Considering the energy required. . . by Yvanhoe · · Score: 1

      ...or one could slow down at 0.999 c and the trip is going to be two minutes longer.

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    2. Re:Considering the energy required. . . by Colonel+Korn · · Score: 1

      ...or one could slow down at 0.999 c and the trip is going to be two minutes longer.

      Except from the perspective of the people on the ship, thanks to the Lorentz factor having the form 1/(1-(v^2)/(c^2))^0.5.

      --
      "I zero-index my hamsters" - Willtor (147206)
    3. Re:Considering the energy required. . . by delt0r · · Score: 3, Interesting

      Some numbers! If the ship is just 100kg with cargo, then you need 6.36e22 J to get to .99999998c assuming 100% efficiency. About 1.4e21 J hits earth everyday from the sun. So a earth sized solar panel will collected the energy required in about 4 and half days. All assuming no energy losses.

      --
      If information wants to be free, why does my internet connection cost so much?
    4. Re:Considering the energy required. . . by Anonymous Coward · · Score: 3, Funny

      Well to you it might be only 2 minutes, but at the destination you will be 5.67 days late and will probably miss your connecting flight.

    5. Re:Considering the energy required. . . by __aasqbs9791 · · Score: 1

      Would that be more like 45 days?

    6. Re:Considering the energy required. . . by delt0r · · Score: 1

      Ops. The energy from the sun in one day is 1.4e22J not 1.4e21. My bad, pesky order of magnitudes.

      --
      If information wants to be free, why does my internet connection cost so much?
    7. Re:Considering the energy required. . . by nine-times · · Score: 1

      I also just fail to see how this is terribly interesting. Sorry, yeah, I like science and it's kind of an interesting little bit of trivia or something, but putting aside the technicalities, doesn't this just boil down to, "If you are going really really really fast and you hit something, it's going to cause damage. Space isn't completely empty, so you're going to hit stuff even in 'empty space'."?

    8. Re:Considering the energy required. . . by Anonymous Coward · · Score: 0

      An earth sized solar panel with 100% efficiency weighting in at 100 kg? Your ideas are intriguing...

    9. Re:Considering the energy required. . . by Anonymous Coward · · Score: 0

      And if we absorb all the energy from the sun striking the Earth we'll also erase global warming! YAY!

    10. Re:Considering the energy required. . . by Carbaholic · · Score: 1

      This solution would also solve our global warming problems!

    11. Re:Considering the energy required. . . by Hurricane78 · · Score: 1

      Have you also calculated what the mass of those 100 kg will be, when it’s at 0.99999998c?

      In light-speed space ship, black hole will be sucked in by YOU!

      --
      Any sufficiently advanced intelligence is indistinguishable from stupidity.
    12. Re:Considering the energy required. . . by Yamata+no+Orochi · · Score: 1

      It's awesome that people just sit around double-checking theoretical math that you may be inclined to post on Slashdot.

      I don't know if I'm joking, or if I'm not.

      Schrödinger's wit?

    13. Re:Considering the energy required. . . by __aasqbs9791 · · Score: 1

      You can't just glance at that and see the problem? If I had actually double checked it, I would have realized he had the wrong exponent on the amount of energy that hits the earth everyday.

      I actually thought that someone bothered to post that at all was pretty interesting. Makes me want to figure out how much energy would hit the inside of a Dyson sphere.

    14. Re:Considering the energy required. . . by coaxial · · Score: 1

      providing sufficient shielding should be a trivial exercise in additional hand-wavium. . . .

      Hand-wavium incidentally is central to the plot of Avatar 2.

    15. Re:Considering the energy required. . . by delt0r · · Score: 1

      The "mass" would be about 700 tons. But that's *inertial* mass not gravitational mass. In fact its probably more accurate to say apparent inertial mass, in the initial rest frame. To the dude on the ship, he/she is their normal mass. But the rest of the universe will look pretty strange.

      --
      If information wants to be free, why does my internet connection cost so much?
    16. Re:Considering the energy required. . . by delt0r · · Score: 1

      1 AU is 149 598 000 km. So the area of a sphere around the sun with a radius of 1 AU is 4*pi*r*r = 2.8e23 m^2. At 1 AU we get about 1.3kW per m^2 above the atmosphere. So the total energy is 3.7e26 Watts. That's converting 4 million tons of mass into energy every second.

      --
      If information wants to be free, why does my internet connection cost so much?
    17. Re:Considering the energy required. . . by delt0r · · Score: 1

      the space ship does need to take the solar panel with it. Since its not really travel size....

      --
      If information wants to be free, why does my internet connection cost so much?
    18. Re:Considering the energy required. . . by Yvanhoe · · Score: 1

      ... for who it will be one microsecond longer

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
  16. Scientist-Schmientist by PolyDwarf · · Score: 1

    "Hydrogen atoms are unavoidable space mines."

    Uhh.. Hey, Mr. Scientist... Ever hear of deflector shields? GOSH!

    Going out on a (geeky) limb... Don't warp drives (again, geek-out time, so just accept they exist a la Star Trek) make a bubble that the ship moves through that goes faster than light, instead of accelerating the ship up to and beyond light speed? I believe I've read that Einstein's theories technically allow for something moving faster than light, if that something can manage to alter their local space-time?

    1. Re:Scientist-Schmientist by maxume · · Score: 1

      Relatively would not give a coherent description of a space time where large amounts of matter moved faster than the speed of light.

      --
      Nerd rage is the funniest rage.
  17. It's not about a velocity of light speed by BadAnalogyGuy · · Score: 2, Funny

    Spacetime is curved, so even if the ship is traveling at 15mph, it reaches its destination in a time indicating FTL travel. The actual distance traveled is much shorter, though.

    This is the stuff you should already know before you apply to Starfleet.

  18. Ramscoop by Kazymyr · · Score: 1

    So use a ramscoop to collect all the hydrogen that's in the way and use it for fuel. Sheesh.

    --
    I hadn't known there were so many idiots in the world until I started using the Internet -Stanislaw Lem
  19. easy solution by nomadic · · Score: 5, Funny

    All you have to do is navigate around the hydrogen atoms.

    1. Re:easy solution by popeyethesailor · · Score: 1

      Yeah, why can't they just put ABS on it?

    2. Re:easy solution by oldspewey · · Score: 1

      Somebody set up us the atom bomb.

      --
      If libertarians are so opposed to effective government, why don't they all move to Somalia?
    3. Re:easy solution by maxwell+demon · · Score: 1

      You think dying in hard gamma radiation is more fun?

      --
      The Tao of math: The numbers you can count are not the real numbers.
    4. Re:easy solution by hypergreatthing · · Score: 1

      At relativistic speeds and with enough distance between the ship and the emitted antimatter, i doubt the crew would get a lethal dose of gamma radiation, besides the fact that you'd still need a ship with enough plating in the front where radiation is a non issue, from the matter annihilation as well as cosmic radiation.

      I really doubt you'd want to be in a ship going anywhere close to light speed without having some sturdy armor between you and the rest of the universe. That and distance at traveling at near light speeds, you can emit the anti matter in the order of miles ahead of you or more. Hell, you can probably collect the energy from the matter/anti-matter collisions and use it to power the ship.

  20. Workaround! by slushdork · · Score: 0, Redundant

    I have a cunning plan to work around this problem: only travel at 99.999997% of the speed of light!

  21. Exactly what I told the first 1.08 x 10^72 by BrentRJones · · Score: 1

    Einsteins that I met on the way to this planet.

    Wally Warp,
        The guy who learned to JUMP to hyperspace and not accelerate into it.

    --
    Help end the use of Sigs. Tomorrow
  22. Faster than light speed - Ludicrous speed by Jetrel · · Score: 1

    What the hell was that? They've gone to plaid!

    --
    If it isn't broke, tinker with it till it is!
  23. True, But Irrelevant... by wintermute3 · · Score: 5, Insightful

    I don't think anyone seriously contemplating relativistic or FTL travel expects to be physically accelerated to such speeds. After all, if stationary interstellar hydrogen is effectively hitting you at teravolt levels, it means that every particle in your body (and the ship) has actually been accelerated to velocities equivalent to the particles in the LHC beam. Not bloody likely. We need warp drive, subspace, wormholes, or something else to solve the problem, not ridiculous conventional acceleration.

    - Michael

    1. Re:True, But Irrelevant... by arielCo · · Score: 5, Funny

      Not bloody likely.

      Likely bloody. Very bloody.

      --
      This post contains no rudeness or derision of any kind. All arguments are friendly. Terms and exclusions may apply.
    2. Re:True, But Irrelevant... by CorporateSuit · · Score: 1

      You're ignoring relativity. Yes, accelerating to that fast in a few seconds would obliterate the person; but done over the course of months/weeks/years, it may not be so messy. From Earth's perspective, they may appear to be a flaming, burning comet screwn across half the solar system, but to them, Earth is simply getting further away, faster.

      Twins paradox, and all that.

      --
      I am the richest astronaut ever to win the superbowl.
    3. Re:True, But Irrelevant... by arminw · · Score: 1, Interesting

      ....We need warp drive, subspace, wormholes, or something else ....

      All of the posts on this subject make the assumptions of a Western scientific/materialistic worldview. There are other views, such as the Bible for example, which open other possibilities for exploring the universe.

      The first and foremost problem to overcome is physical mortality. Jesus Christ claimed to be God and proved this claim by overcoming death. As far as I'm concerned, that would be a prerequisite to being able to explore the vast universe.

      The second problem is to get rid of the limitation of mass. This means that a complex material spaceship would not be needed, in order to leave the earth for other worlds. Read the account of the ascension of Jesus Christ. He did not need a fiery rocket or other kind of vehicle to simply depart the surface of the earth to travel to another world.

      Science has conditioned us to only think in terms of the physical, material part of reality. Einstein taught us that the speed of light is a physical limitation because of energy and mass. He also taught us that matter and energy are directly interchangeable. He had nothing to say on the speed of thought. Does gravity have a speed limit and could it be reversible given the right conditions? We read in the Bible about God and the spirit world and its inhabitants of demons and angels. These cannot be perceived by science. Does that mean they don't exist?

      --
      All theory is gray
    4. Re:True, But Irrelevant... by Anonymous Coward · · Score: 0

      What is religious nutjob doing on Slashdot?

  24. Bussard ramjet or other solutions perhaps? by Anonymous Coward · · Score: 1, Insightful

    In a Bussard Ramjet, the hydrogen is a feature, not a bug, something to be used as fuel. If not that, design the ship aerodynamically (is that the right word?) with a long sharp prow to deflect the hydrogen. Of course, by the time we can actually build such a ship, other solutions will be around. Our current issues will be as antiquated looking as 19th century notions of a flying machine.

  25. 7 teraelectron volts? by Vinegar+Joe · · Score: 3, Funny

    I'll bet that would sting.

    --
    "The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
    1. Re:7 teraelectron volts? by oodaloop · · Score: 1

      Not for very long.

      --
      Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
    2. Re:7 teraelectron volts? by BadAnalogyGuy · · Score: 1

      It's not the voltage, it's the amperage.

    3. Re:7 teraelectron volts? by tehcyder · · Score: 1

      Wuss.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
  26. What would happen? by RedMage · · Score: 1

    Interesting - what WOULD happen if you stood in front of the Large Hadron Collider beam? Does it cut/burn like a laser, or something else? Just wondrin'...

    --
    }#q NO CARRIER
    1. Re:What would happen? by Lord+Ender · · Score: 1

      Interesting - what WOULD happen if you stood in front of the Large Hadron Collider beam

      The collider would shut down for two years due to some component overheating.

      --
      A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
    2. Re:What would happen? by Rockoon · · Score: 1

      It makes block holes out of you.

      --
      "His name was James Damore."
    3. Re:What would happen? by Anonymous Coward · · Score: 0

      I think one of the scientists at the LHC said it would be roughly equivalent to 180 kilograms of TNT exploding in your chest. Ow.

    4. Re:What would happen? by Anonymous Coward · · Score: 0

      The could take a nice proton-ray picture of you.

    5. Re:What would happen? by JamesP · · Score: 2, Informative
      --
      how long until /. fixes commenting on Chrome?
    6. Re:What would happen? by confused+one · · Score: 1

      It would burn a tiny hole in you; but, that wouldn't matter because the radiation flux would kill you within seconds.

    7. Re:What would happen? by Anonymous Coward · · Score: 0

      ...but only in Soviet Russia.

    8. Re:What would happen? by Anonymous Coward · · Score: 0

      Internal or external faults could lead to an asynchronous beam dump, where the extraction kicker field switch-on is not synchronised with the abort gap. Dedicated dilution devices (TCDS, TCDQ) will be placed in front of the extraction septum and the Q4 quadrupole to prevent local equipment damage in the event of such a fault

      Thanks. That clarifies things greatly.

    9. Re:What would happen? by blueg3 · · Score: 1

      Probably the x-ray radiation produced would kill you before you got close enough to stand in front of it.

    10. Re:What would happen? by TooMuchToDo · · Score: 1
      Easy: Bitching on slashdot about the LHC

      Hard: Actually building the LHC

    11. Re:What would happen? by Anonymous Coward · · Score: 0

      Others have covered the "You die" aspect, but as far as the energy goes, consider it approximately the same as burning 10 liters of vegetable oil. (See Mythbusters for an idea what sort of conflagration that could be.)

    12. Re:What would happen? by Zerth · · Score: 1

      Anatoli Bugorski

      After sticking his head in the beam, he looked like this

      It was almost painless. It just killed every cell along the path, which wasn't too bad until the skin peeled off. He's lived nearly 30 years, even finished his PhD, despite receiving enough radiation to kill a person if it were spread evenly.

    13. Re:What would happen? by dissy · · Score: 1

      Interesting - what WOULD happen if you stood in front of the Large Hadron Collider beam

      The collider would shut down for two years due to some component overheating.

      Hey now, no need to resort to name calling the GP a 'component' ;}

      The good news is that at the temperatures the environment is kept at, there won't be too much of a mess to clean off the walls left by whomever was standing there.

    14. Re:What would happen? by ceoyoyo · · Score: 1

      It's kind of like a high powered laser. It doesn't so much cut holes in you as blow holes in you. The beam itself would make a fairly small hole but the debris from those collisions would be like an explosion.

    15. Re:What would happen? by Anonymous Coward · · Score: 0

      You won't be having children, but seeing this is slashdot that shouldn't be too much of a worry.

  27. HAHA SHIELDS by wtbname · · Score: 1

    HAH Noobs thats what the NAVIGATION SHI... aww damnit.

  28. Current Science by Anonymous Coward · · Score: 0

    How can the earth be round? Would one not fall off? Preposterous!

    1. Re:Current Science by cmiller173 · · Score: 1

      Of course you would not fall off, gravity rays from the dome of the heavens are constantly pushing you down to the surface of the earth.

  29. Eggheads Love This Hooey by Anonymous Coward · · Score: 0

    I however, do not. Let's try to build a ship that can get to mars with 1G constant acceleration/decceleration first. And let's figure out how to install some fairly massive shielding against the already damaging background radiation in our non-relativistic vehicle. These problem is hard enough.

    Eggheads get all excited about another order of magnitude or another significant digit. Yeah, they are out there at the edge of human knowledge expanding the boundaries. Great. Applications need to catch up with them quite a lot.

  30. Fascinating limitation by CrimsonAvenger · · Score: 3, Insightful

    So, what he's saying is that the interstellar hydrogen density will limit us to no more than about 9600 light years nonstop at a continuous 1g acceleration/deceleration.

    Given that even a matter/antimatter conversion drive would require about 116,000,000 tons of reaction mass (half antimatter) for every ton of payload, it would seem that we're going to be hitting a great many limits long before this particular limit begins to be meaningful.

    --

    "I do not agree with what you say, but I will defend to the death your right to say it"
    1. Re:Fascinating limitation by selven · · Score: 1

      It's not just hydrogen atoms blowing up your ship, it's friction. Eventually, you're going to hit an equilibrium where the force of oncoming hydrogen atoms will match your thrust. Then you're stuck moving at one speed, provided you can stop your ship from overheating.

    2. Re:Fascinating limitation by Anonymous Coward · · Score: 0

      Wasn't the point of Antimatter reactions that you could carry just the anti-matter, and suck the real-matter part of the fuel out of the interstellar medium with something like a ram scoop?

    3. Re:Fascinating limitation by Anonymous Coward · · Score: 0

      Half your reaction mass being antimater would be incredibly inefficient.
      You want to use the energy released by mixing your matter and antimatter to throw more matter out the back of the ship.
      You are otherwise just shining a very bright gamma ray torch into space.

      You could even use the hydrogen you have just been scooping up.

  31. incorrect by Atreide · · Score: 1

    AFAIK Luke, Han and friends did not collide with some giant Hydrogen ollider.
    They just nearly collide with a giant artificial moon.

    --
    The world belongs to those who get up early. - I'm far from being the king of Earth then :-(
    1. Re:incorrect by camperdave · · Score: 1

      Ah, but that ain't this galaxy. That was one far, far away, and obviously devoid of interstellar hydrogen.

      --
      When our name is on the back of your car, we're behind you all the way!
  32. Easily fixed! by get+quad · · Score: 1

    How about a giant windshield wiper wiping slightly faster than the speed of light? amirite? amirite?

    --
    "To err is human, to mod Funny divine."
  33. Important fact missing by alewar · · Score: 1

    According to the theories developed by Tessa Wendel, once you are traveling faster than the speed of light the nature of gravity changes from attraction to repulsion. This means that a spaceship traveling that fast would be effectively shielded from small objects by the gravitational force.

    1. Re:Important fact missing by __aasqbs9791 · · Score: 1

      ...once you are traveling faster than the speed of light the nature of gravity changes from attraction to repulsion. This means that a spaceship traveling that fast would be effectively shielded from small objects by the gravitational force.

      I must have missed the day where they taught us that "99.999998 per cent of the speed of light" was faster than the speed of light.

  34. This is a problem?!? by wbav · · Score: 1

    It seems like this would be a solution to a problem, mainly power. Granted, it is power already spent by the ship, but is there any reason why it couldn't be shunted back into the system? It seems that it would mitigate the problem of power requirements for FLT.

    --

    =================
    Unix is very user friendly, it's just picky about who its friends are.
  35. news? by Anonymous Coward · · Score: 0

    when i was young (30years ago ... *snif*) it was already quite well known that even with 10% light speed interstellar matter tend to heat up your spaceship until destruction .... so whats new about that with even faster speeds?

  36. This is, of course, impossible. by asdf7890 · · Score: 1

    This is, of course, impossible - which is why the advertising executives of the star system of Bastablon came up with this slogan: "If you've done six impossible things this morning, why not round it off with breakfast at Milliways, the Restaurant at the End of the Universe?"

  37. All that says is that we can't hit lightspeed... by VShael · · Score: 1

    through the medium of interstellar space.

    I'm pretty sure I can't travel at 30,000 mph through the ocean either. Through space, not as big a problem.

    Most SF geeks would agree that if we're ever going to exceed C, we won't be doing it in meatspace.

  38. Slight difference in density by AJWM · · Score: 1

    The protons in the LHC are a little closer together than those in interstellar space. Density in interstellar space is about 1 atom per cubic centimeter. I can't readily find a number for the cross-sectional area of the LHC beam, but it is surely less than 1 cm^2 and each ring has 2835 x 10^11 protons over its 27 km length -- or better than 10^8 protons per cubic centimeter.

    So no, it's not quite like standing in front of the beam from the LHC, not by a factor of a hundred million.

    --
    -- Alastair
    1. Re:Slight difference in density by nani+popoki · · Score: 1

      Are you sure about that *in the reference frame of the vehicle*?

      I'm not a physicist, but won't the Lorentz contraction come into play? At these speeds, 1 cm in the direction of travel as viewed from the ship's reference frame would be something like 1.6 meters, if I did the math right. So the effective density would be 1600 times higher than as viewed by a stationary observer.

  39. relativity by StripedCow · · Score: 1

    I guess that we're just lucky that Earth is moving at roughly the same speed as those hydrogen atoms.

    --
    If Pandora's box is destined to be opened, *I* want to be the one to open it.
  40. Lightspeed is so 1960's. by gimmebeer · · Score: 1

    Why don't we talk about big robots with lightbulbs for heads while we're at it? Even at lightspeed, it would take us 100,000 years to reach the other side of just our OWN galaxy. Sure, it seems infinitely fast, but it's really not going to get us anywhere all that interesting in a single lifetime. What we NEED, is to clone Hawking's brain a few thousand times, hook them all up to a central logic unit, then set them to work on a real Warp Drive.

    1. Re:Lightspeed is so 1960's. by Thanatos81 · · Score: 1

      You're talking a Beowulf cluster of Hawking-brains? I for one welcome our new Skynet!

    2. Re:Lightspeed is so 1960's. by Rockoon · · Score: 2, Informative

      Sure, it seems infinitely fast, but it's really not going to get us anywhere all that interesting in a single lifetime.

      For the personal traveling at that speed, it most certainly WILL be a single lifetime. In fact, the trip would seem to them to be instantaneous.

      --
      "His name was James Damore."
    3. Re:Lightspeed is so 1960's. by Anonymous Coward · · Score: 0

      I think the ARTICLE meant STUPIDITY (Score:?=sorry to bro)
      by myspace-cn (1094627)

      Come on, some of you remember.

      the two most common elements in the universe?

    4. Re:Lightspeed is so 1960's. by timholman · · Score: 1

      For the personal traveling at that speed, it most certainly WILL be a single lifetime. In fact, the trip would seem to them to be instantaneous.

      And that's the point that so many people miss. Faster-than-light travel is absolutely possible from the viewpoint of the traveler, given sufficient energy. At a velocity close enough to light, you could cross the galaxy in a matter of days, and visit thousands of different stars and planets in a subjective lifetime. You could even travel to another galaxy. It's all a function of your maximum velocity and maximum acceleration.

      The only drawback is that you can never go home. Every leg of the trip would be one-way.

    5. Re:Lightspeed is so 1960's. by archangel9 · · Score: 1

      The only drawback is that you can never go home. Every leg of the trip would be one-way.

      who says you can never go home?

      oh, that's right. science. DAMMIT!

    6. Re:Lightspeed is so 1960's. by mdm-adph · · Score: 1

      I believe that fuel source/supply is also a concern. :P

      --
      It is by my will alone my thoughts acquire motion; it is by the juice of the coffee bean that the thoughts acquire speed
    7. Re:Lightspeed is so 1960's. by osu-neko · · Score: 1

      I believe that fuel source/supply is also a concern. :P

      The universe is flinging hydrogen at your with such force people are concerned about you surviving the onslaught, and you can't find a fuel source? XD

      --
      "Convictions are more dangerous enemies of truth than lies."
    8. Re:Lightspeed is so 1960's. by mdm-adph · · Score: 1

      Obviously not -- the petroleum industry has been telling us for decades now that hydrogen is an inefficient and unmarketable source of fuel.

      Personally, I'm waiting around a few million years until our solar system passes through the 10W-40 nebula.

      --
      It is by my will alone my thoughts acquire motion; it is by the juice of the coffee bean that the thoughts acquire speed
  41. Ask the Ricers! by Anonymous Coward · · Score: 0

    You need a scoop AND a fin.

  42. Ionized hydrogen? by durrr · · Score: 1

    Wouldn't the hydrogen exist in ionized forms, and thus be possible to divert by electric fields? A 99.999% spaceship would probably have enough of an energy supply to power the LHC a few times over and thus be able to shield the significant part of the craft from any LHC strenght radiation?

    1. Re:Ionized hydrogen? by k8to · · Score: 1

      Using electromagenetic radiation to deflect particles when you're travelling at 99.999% of the same radiation... well, it is unlikely to help that much.

      Perhaps you could send a drone or some shiznits way out in front of the ship, emitting the fields, but i'm not sure what's going to protect it.

      --
      -josh
    2. Re:Ionized hydrogen? by osu-neko · · Score: 1

      Perhaps you could send a drone or some shiznits way out in front of the ship, emitting the fields, but i'm not sure what's going to protect it.

      Another problem solved by recursion!

      --
      "Convictions are more dangerous enemies of truth than lies."
  43. Sounds like good news to me by Anonymous Coward · · Score: 0

    One of the problems with traveling in interstellar space is that there's not a lot of reaction mass out there to propel you. But if the hydrogen is dense enough to cause drag, it's dense enough to use as fuel too. So this sounds like good news for interstellar travel.

  44. Physician, not physicist by Al+Al+Cool+J · · Score: 2, Funny

    What does this guy know about space travel? He's a prof at a medical school, FFS. This is rocket science, not brain surgery!

    1. Re:Physician, not physicist by danhuby · · Score: 1

      He's a Professor of Radiology and he's talking about ionising radiation. It seems to be within his field?

    2. Re:Physician, not physicist by Al+Al+Cool+J · · Score: 1

      If the method of space travel being discussed doesn't result in high-energy collisions with hydrogen atoms in the first place, as is the case with a Star Trek like warp field (aka an Alcubierre drive), then he clearly isn't qualified. Every write-up I've seen on this guy's analysis, including TFA, is appended by notes explaining various things this guy omitted or didn't think of.

      Frankly, whenever somebody claims to have proven that something is impossible, usually the only thing they have proven is that they are unimaginative dolt.

    3. Re:Physician, not physicist by stewhites · · Score: 1

      Damnit Jim, i'm a doctor, not an engineer!

    4. Re:Physician, not physicist by garompeta · · Score: 1

      Unless he is doing pet scans travelling at light speed, I don't think it is within his field.

    5. Re:Physician, not physicist by garompeta · · Score: 1

      Bush: "hehe, for some of this question you got to be a rocket surgeon" http://www.youtube.com/watch?v=P52bmJXYQPQ

    6. Re:Physician, not physicist by osu-neko · · Score: 1

      One person's explanation of why something can't be done is another person's catalog of problems to solve in order to do it.

      --
      "Convictions are more dangerous enemies of truth than lies."
    7. Re:Physician, not physicist by Anonymous Coward · · Score: 0

      I'm too lazy to look up this guy's CV, but radiologists are usually experts in interpreting X-ray, CT, MRI, and PET images. I.e. more "is this blurry thing something pathological or just my imagination?" and "what type of radioactive dye will this patient best tolerate?" rather than building or designing such devices. He probably does understand the underlying principles, but less so than an engineer or physicist.

    8. Re:Physician, not physicist by Anonymous Coward · · Score: 0

      Oblig Mitchell and Webb:

      http://www.youtube.com/watch?v=THNPmhBl-8I

    9. Re:Physician, not physicist by Anonymous Coward · · Score: 0

      Clarke's First Law

      When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

  45. Warp drives don't exist by SmallFurryCreature · · Score: 0, Troll

    I know, it is a shocker but I found out when I went outside that A: the light, it burns and B: Star Trek ain't real.

    --

    MMO Quests are like orgasms:

    You may solo them, I prefer them in a group.

    1. Re:Warp drives don't exist by TooMuchToDo · · Score: 2, Insightful

      B: Star Trek ain't real.

      But science keeps coming up with things based on it: cellphones, PDAs, netbooks, flash memory, etc. Everyone needs inspiration from something.

  46. I'm disapointed by BESTouff · · Score: 1

    We don't need 99.99999% of the speed of light. We need FTL (Faster Than Light), for before 2012 please !

  47. Economics by TrumpetPower! · · Score: 4, Insightful

    Interstellar travel is fundamentally an economic paradox — ignoring, of course, such fantasies as Warp drives.

    Sending a Shuttle-sized craft to Alpha Centauri in a matter of years would require roughly the current total energy consumption of humanity.

    Only when our civilization advances to the point that we harness a significant portion of the Sun’s total energy output would the energy budget for interstellar travel approximate the same proportion of the energy budget we spend today on interplanetary missions.

    One can suggest “sleeper ships,” but building mechanical devices that will survive thousands of years is as hard a problem as throwing them across light years of distance. Any gas will leak out of any container in such a timeframe, and no plastic or rubber seal would last a fraction of the time necessary. The next thought is to provide power to the ship during the long journey, but you need as much total energy as for getting there fast — and, if you can comfortably survive for millennia in interstellar space, why even bother with stars in the first place?

    Oh — and the Fermi Paradox applies especially well. Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period.

    Interstellar travel makes for great space opera, but it has no more bearing on reality than unicorns and dragons.

    Cheers,

    b&

    --
    All but God can prove this sentence true.
    1. Re:Economics by Anonymous Coward · · Score: 0

      Interstellar travel makes for great space opera, but it has no more bearing on reality than unicorns and dragons.

      Great... you're telling me that the Unicorns and Dragons have already beat us in the race for interstellar travel? It would explain why they're no longer around my house though...

    2. Re:Economics by Anonymous Coward · · Score: 0

      And only if we get some serious life extension technologies going too. We have the life span of a gnat. We are not meant for space. We're too fragile too.

      Realistically, we only have 10 to 20 years of useful life. 0-23 is learning time, since a bachelor's is a minimum these days, and would you send high schoolers in space?
      From about 23 to 43 you get a nice useful span, peaking at about 30. Then after about 43, you rapidly disintegrate. Your brain gets slower, your body bigger, slower and unhealthy. You can deny reality all you want, I'm 38, and I *know* this is true, I can *feel* it.

      Even if we get the fantastic (in the original sense of the word, that is, fantasy-based) space technologies working, you still end up with the fact that most people you know will be dead by the time you get anywhere and back in space. Space is big, we are not.

      We do not have the technology or the energy resources to do anything in space other than floating around a bit, or sending small probes here and there. We are still at the 19th century level of technology, with a few refinements plus electronics. That's it. Our energy comes from a few hundred cubic miles of underground plant goo. We burn it. That's it. That's our technology. Nuclear? Give me a break. These are steam turbines. We burn finite amounts of uranium to do it. Coal? Well, more plant goo.

      Combine that with the fact that most people are basically dangerous children in small, fragile bodies, and space is the least of our concerns. We can't do anything up there because we fall apart, and there's nothing to gain from space because the only "space" we have access to is barely out of our atmosphere. There's nothing in space. It's a big vacuum.

      Space is a non-issue until we live a lot longer and have real energy resources and real medical technology.

    3. Re:Economics by martas · · Score: 1

      you're the kind of guy who predicts that nobody would ever need more than 640k of memory, aren't you? or that airplanes have no military applications whatsoever? or that everything that can be invented, has been invented? (the last 2 are from the 19th century, if i'm not mistaken)

    4. Re:Economics by Dr.Syshalt · · Score: 1

      Oh — and the Fermi Paradox applies especially well. Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period.

      There is no sign that it hasn't been colonized at some point either - we just don't know. Civilizations rise and die, their parts unite and then they fall into pieces. We, humans, could be remnants of some ancient aliens colony too.

    5. Re:Economics by hypergreatthing · · Score: 1

      Who say's it's not colonized?

    6. Re:Economics by CharlyFoxtrot · · Score: 1

      If we're assuming technology capable of interstellar travel why would we have to go ourselves ? Simply send a ship capable of growing a human body from stem cells and imprinting it with a personality once you get there. The ship itself could then stay mostly inert with a small core active to preserve the biological materials, containment could be done with a living biological "seal" instead of rubber and plastics. To avoid mutation in the biological components you could coat the outside of the ship with a "shield" of a 100m or so of good old H2O.

      --
      If all else fails, immortality can always be assured by spectacular error.
    7. Re:Economics by LWATCDR · · Score: 1

      "Oh — and the Fermi Paradox applies especially well. Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period."
      Unless we are the first.

      --
      See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
    8. Re:Economics by Mr+Chulito · · Score: 1

      Please ignore my ignorance but can't we use this to our advantage?.... if this hydro is creating so many volts, why can't we find a way to just harvest it? and use it for the propulsion systems at the same time giving us more power with less on-board resources?...

    9. Re:Economics by Anonymous Coward · · Score: 0

      "Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period."

      Someone has to be the first to evolve. Maybe it's us.

    10. Re:Economics by Ihlosi · · Score: 1
      Sending a Shuttle-sized craft to Alpha Centauri in a matter of years would require roughly the current total energy consumption of humanity.

      Err ... I don't think that accelerating a shuttle-sized craft at 4 or 5g requires the current total energy consumption of humanity. Probably only a tiny, tiny fraction of it. The only problem is coming up with a propulsion method that can provide such acceleration for long periods of time, and a nuclear reactor (fission/fusion/antimatter) small enough to fit on the craft.

      Only when our civilization advances to the point that we harness a significant portion of the Sun's total energy output

      Screw the sun. Way too bulky and pretty much useless once you get past Neptune or so. It's a bit like flight - you want the concept (aerodynamic lift/nuclear fusion), but not the actual implementation (flapping wings/gravitational confinement), but something that you can actually build.

      One can suggest "sleeper ships", but building mechanical devices that will survive thousands of years is as hard a problem as throwing them across light years of distance.

      Thousands of years? Are you proposing that someone rows that thing to Alpha Centauri? Unless we can go at least 0.01c, we shouldn't be thinking about leaving our solar system just yet, and at 0.01c the trip is going to be much shorter than thousands of years. At 0.1c it should be around a hundred years.

      The next thought is to provide power to the ship during the long journey,

      Big honkin' reactor. You might even be able to pull it off with a fission reactor, but I'd wait until we have either figured out fusion or come to the conclusion that artificial fusion reactors aren't feasible (let's hope not).

      and, if you can comfortably survive for millennia in interstellar space, why even bother with stars in the first place?

      Well, a sleeper ship isn't exactly "surviving". That'd be like saying "ok, if you have an aircraft, why bother with the ground".

      Oh -- and the Fermi Paradox applies especially well. Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period.

      Well, if you change the variables a little, it could take longer. Maybe it's not possible to colonize the galaxy in the way suggested by that approximation, since the stars aren't distributed evenly?

    11. Re:Economics by Shompol · · Score: 1

      You know, finding a way to India across Atlantic was an opera only a few hundred years ago, especially given the dangers of falling off the edge of the Earth.

    12. Re:Economics by gmuslera · · Score: 1

      You are assuming that we will reach certain technology, and none else that goes in the same direction. But we could get advancements in some areas that could change the equation:
      - Energy: Efficient mass-energy conversion could give us enough energy to get pretty far, and maybe another source of energy can be used too.
      - Distance: Maybe walking all the way, step by step, to the next star,is the only way ever to get there. Maybe not.
      - Long trips: Takes a lot of time to get somewhere else. What if we take time out of concerns? Send entire colonies to get somewhere else at a relatively slow speed, and dont care if it takes a hundred years if they could be sleeping, or have enough resources to make it awake.
      - AI: dont send humans, send intelligent enough machines (and be patient, very patient)

      Regarding Fermi Paradox, is too homocentric. Exploration, reproducing till filling all the available space and resources, running away if we cant solve troubles here, etc, could be our way of thinking, but maybe not the one in other places of the universe. They could have the technology to move somewhere else, but only use it if a big enough disaster is about to strike.

    13. Re:Economics by drooling-dog · · Score: 1

      Bringing reality into the picture isn't going to make you very popular in these parts.

    14. Re:Economics by drooling-dog · · Score: 1

      You're the kind of guy who believes that physics and economics places no constraints at all on what is achievable, aren't you?

    15. Re:Economics by Anonymous Coward · · Score: 0

      The Fermi Paradox assumes that advance civilizations have the same goals as primitive civilizations. I think the probability is small that 100% of all civilization die some horrible death right before they achieve intersellar flight. I believe there are only two probable answers: 1) There is a civilization that is destroying other civilizations right before they achieve interstellar flight or all civilizations find some other goal that is far more interesting. I vote for the far more interesting goal.

    16. Re:Economics by Anonymous Coward · · Score: 0

      It's easy to dismiss the possibilities of the future when the technology hasn't been invented yet.

      If you'd take a slightly more optimistic view of the possibilities that are yet to come, you might join the camp that actually wants humans to progress outside the confines of what is economically feasible.

      Not everything in life, or humanity for that matter, should revolve around the almighty $. Pointing out the limitations of humanity doesn't change the landscape. It's like reminding us the Sun is in the sky.

    17. Re:Economics by BZ · · Score: 2, Interesting

      > I don't think that accelerating a shuttle-sized craft at 4 or 5g requires the current
      > total energy consumption of humanity

      Let's call it 4g in the spacecraft's frame, or a force of 4g*m (rest mass). Doing a quick special-relativistic approximation to the process, I get:

          v = c * tanh(4gt/c)

      as the spacecraft's velocity in the earth's frame as a function of time. Then its position is:

          s = c^2/(4g) * ln(cosh(4gt/c))

      or in other words:

          cosh(4gt/c) = exp(s*4g/c^2)

      Plugging in s = 2.19 ly (half the distance to Alpha Centauri) we get:

          t = 2.36 years

      or so. At that point you turn over and start decelerating.

      The peak power draw in this setup will be at this t=2.36 year mark, at which point we have v = 0.99999999c if my calculations are right. dE/dt = mva*gamma or so. Gamma is 8500 or so in this case. So we're looking at about 1e14 watts per kilogram. The space shuttle's mass is about 2e6 kilograms, so you're talking 2e20 watts.

      World average power consumption in 2008 was 1.5e13 watts according to . So in fact peak power draw for your proposed constant-4g trip would be about 10,000,000 times more than the power consumption of all of humanity today.

      Never underestimate the energy of macroscopic objects traveling at near-lightspeed.

    18. Re:Economics by BZ · · Score: 1
    19. Re:Economics by Anonymous Coward · · Score: 0

      I propose we build a giant space ship with sufficient mass that it has enought gravitational force to retain it's own atmosphere, then put it in orbit around a fast moving star swinging around the edge of a roaming galaxy, then just hitch-hike our way through the universe. We could have the entire human race ride on it and in only a few generations you can only imagine how much of the universe we could cover!

      I do recommend putting a smaller space craft in orbit around the larger one to provide recreational space travel during the long trip.

    20. Re:Economics by khallow · · Score: 1

      Sending a Shuttle-sized craft to Alpha Centauri in a matter of years would require roughly the current total energy consumption of humanity.

      It depends on the number of years, that is, how fast you are going. For example, 100 metric tons (Shuttle sized) going half the speed of light would have a kinetic energy of around 390 billion megawatt hours (MwH) (here, kinetic energy, K = mc^2*(1/SQRT(1-v^2/c^2) -1) where m is the mass, c speed of light, and v the velocity of the vehicle). That's roughly 3 years of global power generation at 15 trillion watts average generation (current global energy consumption). If it were traveling at 0.1c, then the kinetic energy would be roughly 13 billion MwH which would be a bit over a month of global power generation. You have to double those figures (since you need to slow down at the other end) to yield roughly 6 years and 2 months of power generation respectively.

      if you can comfortably survive for millennia in interstellar space, why even bother with stars in the first place?

      Because that is where the accessible energy and matter are.

    21. Re:Economics by martas · · Score: 1

      no, but i do think that all those limits apply to what's possible at any given point in time. considering how quickly theories are discarded in physics, and how frequently technology makes economically infeasible things feasible, i'd be very hesitant to claim that something can never be done. and yes, this even applies to the really-really-theoretically-impossible things like faster than light travel.

    22. Re:Economics by furby076 · · Score: 1

      Interstellar travel makes for great space opera, but it has no more bearing on reality than unicorns and dragons

      While this is true, and likely to remain true for a long long long LONG freaking time if ever....and I know it is true...it is still depressing and sinks the heart reading it :(

      It also makes it that much more important that we take care of this rock we call home

      --

      I do not support "The Man". I also do not support your irrational stupidity
    23. Re:Economics by HermDog · · Score: 1

      Interstellar travel makes for great space opera, but it has no more bearing on reality than unicorns and dragons.

      Oh, you can scoff. The only reason why the entire galaxy wasn't colonized millions of years ago is because, as everyone knows, unicorns and dragons lack opposable thumbs and are consequently a little behind on drawing up the specs for their interstellar sleeper warp-drive jumpships.

      --
      JADBP
    24. Re:Economics by osu-neko · · Score: 2, Insightful

      Long trips: Takes a lot of time to get somewhere else. What if we take time out of concerns? Send entire colonies to get somewhere else at a relatively slow speed, and dont care if it takes a hundred years if they could be sleeping, or have enough resources to make it awake.

      ...ala generation ships. Here's the problem: Anyone who can make a habitat you can live in for that long has mastered the art of living in space. The last thing such a civilization is going to desire, having successfully climbed out of the gravitational hole they were born in, is climb into another one. So, they might visit other stars, but they wouldn't be "sending entire colonies", they'd be sending tourists.

      --
      "Convictions are more dangerous enemies of truth than lies."
    25. Re:Economics by osu-neko · · Score: 1

      Well, if you change the variables a little, it could take longer.

      Not significantly longer, geologically speaking. It's an exponential thing. Like the man who asks for one grain of rice the first day, two the second day, four the third day, etc. Change that to weeks, or months, or years, or centuries, and it takes longer for it to equal the entire agriculture output of the empire, but the difference in time isn't significant when talking in the timescale of geological eras, because the exponential nature of the function eventually overwhelms the lengthy delays in getting the ball rolling. If you don't fiddle the variables to the point that it takes any planet a geological age to produce its first colony, the entire galaxy ends up colonized in a timescale smaller than a geological age.

      --
      "Convictions are more dangerous enemies of truth than lies."
    26. Re:Economics by Grishnakh · · Score: 1

      - Long trips: Takes a lot of time to get somewhere else. What if we take time out of concerns? Send entire colonies to get somewhere else at a relatively slow speed, and dont care if it takes a hundred years if they could be sleeping, or have enough resources to make it awake.

      There's a few problems with this.
      1) You need a place to send these colonies TO. At our current rate of technology, it'll take a few thousand years to send a probe to Alpha Centauri, the nearest star, and have it report back if there's any place there worth sending a colony ship to. The only alternative is sending a colony ship to travel from star to star until they find a place worth stopping at. That's going to require a lot of energy for all the acceleration and deceleration cycles, a lot more than a single trip from Earth to one star.

      2) Sending a colony ship will require tons of resources to build this ship. Unless Earth is on its last legs, and all surviving humans are going to be hitching a ride on this colony ship, who's going to bother expending all their resources to help send a small number of people in search of a new home?

      Regarding Fermi Paradox, is too homocentric. Exploration, reproducing till filling all the available space and resources, running away if we cant solve troubles here, etc, could be our way of thinking, but maybe not the one in other places of the universe. They could have the technology to move somewhere else, but only use it if a big enough disaster is about to strike.

      I think any civilization with the technology to colonize other worlds would easily be able to terraform various worlds they encounter. With the right technology, there's tons of resources in space; you don't NEED a planet that's just like Earth; you can alter an existing world to be the paradise of your choice. Sure, you might need to move a planet to a new orbit, change its atmosphere, etc., but if you have the technology to travel across the galaxy, those things shouldn't be hard. Therefore, the ETs might be out there and already developed an interstellar civilization, without having had to bother to travel all the way here and bother us. Plus, they might simply not be interested in us, or maybe they've already visited, with a small accident in Roswell, New Mexico, and decided we're not worth establishing official contact with.

    27. Re:Economics by Ihlosi · · Score: 1
      Never underestimate the energy of macroscopic objects traveling at near-lightspeed.

      You don't need to go anywhere near lightspeed (and we have another article here describing some of the problems you might face if you try, like 7 TeV hydrogen atoms). 0.1c would be pretty good for starters. It might take a few decades, but hey, you're going to another star system. That alone should be worth the wait. For an unmanned probe, even slower speeds would be ok. We're already waiting years for a probe to reach, say, Pluto. If we could send a probe to AC in 80 years or so, that'd be worth it.

    28. Re:Economics by osu-neko · · Score: 1

      Maybe it's not possible to colonize the galaxy in the way suggested by that approximation, since the stars aren't distributed evenly?

      Oh, and, actually, they pretty much are. Spiral arms are optical phenomena due to the locations of the newest and brightest stars (which aren't really likely to have attractive planets for colonization in any case). Sun-like stars are as evenly distributed through the galactic pancake as food coloring is in your purple pancakse after you spend 10 minutes mixing the batter.

      --
      "Convictions are more dangerous enemies of truth than lies."
    29. Re:Economics by Grishnakh · · Score: 1

      Most dragon drawings I've seen show something close to opposable thumbs. However, the dragons have trouble with spaceflight because every time they try to draw up specs for their warp-drive jumpships, they inevitably sneeze and burn up the plans.

    30. Re:Economics by amorsen · · Score: 1

      The eV are created directly from the ships kinetic energy. You can put it back with the propulsion system, but there will always be a loss. What's worse is that you lose momentum, which can only be replaced by catching the incoming particles and accelerating them out the back -- or by expending valuable reaction mass.

      --
      Finally! A year of moderation! Ready for 2019?
    31. Re:Economics by ceoyoyo · · Score: 1

      GGP specified the trip was to take years, not decades.

    32. Re:Economics by Ihlosi · · Score: 1
      GGP specified the trip was to take years, not decades.

      Still, no need to go anywhere near 0.99c even if the trip is supposed to take less than a decade.

    33. Re:Economics by ceoyoyo · · Score: 1

      If you're going to have a realistic acceleration (or even an unrealistic one like 4 or 5 g, as specified) and you want to go 4+ light years in less than a decade you're going to have to go pretty close to the speed of light.

    34. Re:Economics by BZ · · Score: 2, Informative

      > You don't need to go anywhere near lightspeed

      The grandparent specifically said constant 4g boost to Alpha Centauri. That ends up near lightspeed.

      But even if you restrict to just getting there in "years" (as great-grandparent did), you end up with an average speed of close to 0.5c if you want to stay under 10 years... Which means your top speed needs to be pretty close to c.

    35. Re:Economics by Anonymous Coward · · Score: 0

      Your energy requirements and Fermi Paradox statements are contradictory. The mathematical colonization speed studies are assuming best-case Von Neumann probes... and that really is a lot of assumption, including assuming tech that we're currently not even sure is possible.

      Using your own requirement of at least a Type I on the http://en.wikipedia.org/wiki/Kardashev_scale and on the way to Type II, it'd take far, far longer. If we don't have magic nanotech and don't find 'perfect' target planets, a colony ship is going to take a few thousand years before it can even begin to try living on a new planet. And once it does get to the point where it could reasonably quickly colonize a planet, it probably wouldn't be in much of a hurry; this would be a civilization many generations removed from ours, retaining our tech... they probably aren't going to care to breed fast. It could take them hundreds of thousands of years to 'fill' a new planet; more if the system has several good planets. And then they'd need to climb all the way up to Type II on their own before considering sending colony ships of their own.

      Considering that spacefaring species may not be in any kind of hurry to spread past the first dozen colony systems, a better expression of the Fermi Paradox would be "where are all the Dyson spheres?" (or at least the intermediate stages of construction, which would be detectable from here). We've only just started to consider looking for those. The distribution of them, or the lack of them, would tell us a lot about the frequency of life that reaches that level. I assume intelligent life isn't unique to the universe, but it could still be relatively rare/young enough that there are only a few in each galaxy like ours. Especially if it takes a lot of generations of star birth/dead to amass enough of the heavier elements; considering our own star has a lifespan of billions of years, we really haven't been through all that many star generations.

    36. Re:Economics by Anonymous Coward · · Score: 0

      Try to imagine yourself in the Cretaceous Period. You get your first look at this "six foot turkey" as you enter a clearing. He moves like a bird, lightly, bobbing his head. And you keep still because you think that maybe his visual acuity is based on movement like T-Rex - he'll lose you if you don't move. But no, not Velociraptor. You stare at him, and he just stares right back. And that's when the attack comes. Not from the front, but from the side, *whoosh* from the other two 'raptors you didn't even know were there. Because Velociraptor's a pack hunter, you see, he uses coordinated attack patterns and he is out in force today. And he slashes at you with this... a six-inch retractable claw, like a razor, on the the middle toe. He doesn't bother to bite your jugular like a lion, say... no no. He slashes at you here... or here... or maybe across the belly, spilling your intestines. The point is... you are alive when they start to eat you. So you know... wipe out all life on the planet and set up an Oort cloud to isolate them.

    37. Re:Economics by Anonymous Coward · · Score: 0

      "Any gas will leak out of any container in such a timeframe, and no plastic or rubber seal would last a fraction of the time necessary."

      Gas pockets in ice cores or fossilized amber?

    38. Re:Economics by Ihlosi · · Score: 1
      If you're going to have a realistic acceleration (or even an unrealistic one like 4 or 5 g, as specified) and you want to go 4+ light years in less than a decade you're going to have to go pretty close to the speed of light.

      Since the Lorentz factor is 1 / sqrt(1 - v^2/c^2), there's a huge difference between going, say, 0.8c and 0.999c in terms of relativistic effects, even though the object in question is barely moving 25% faster from a stationary viewpoint.

      A top speed of 0.8c would be pretty impressive and allow to make the trip in less than a decade given sufficient acceleration, without the need to deal with overly pesky relativistic effects (Lorentz factor of 1.667 compared to 22.4 for 0.999c).

    39. Re:Economics by Ihlosi · · Score: 1
      Which means your top speed needs to be pretty close to c.

      The formula for the Lorentz factor is 1 / sqrt(1 - v^2/c^2). And there's a huge difference between being close to c (0.9c) and being close to c (0.999c): The Lorentz factor for the former case is a measly 2.3, while it's 22.4 for the latter case even though the object in question is only moving about 10% faster.

      And then there's the problem of 9 TeV hydrogen atoms hitting your windshield if you go fast enough. Not something you really want to deal with if you can avoid the problem altogether by making the trip take 10% longer.

    40. Re:Economics by BZ · · Score: 1

      Yes, I'm well aware of what the formula for gamma is. If you note, in the above calculation gamma was about 8500 or so. If you drop down to 0.5c, gamma is closer to 1.2, and the top speed is about half, so the power draw drops by a factor of about 1.7e4. So instead of being 1e7 the total power production of humanity right now it's "only" 1e3.

      So yes, ultra-relativistic speeds involve all sorts of problems, but even getting up to anything resembling relativistic speeds for a macroscopic object requires huge amounts of energy.

      The other way to think of this is that getting up to a speed k*c requires you to completely convert a fraction of your mass equal to "1/sqrt(1-k^2) - 1" to energy. If k == 0.1, that's about 0.5%. Uranium fission converts about 0.1% of the mass each fissioned nucleus into energy, so you can't get to 0.1c using fission if you're carrying along all the fuel. Deuterium+tritium fusion converts about 0.3% of the mass of the original nucleons to energy for each event, so it's not quite good enough either.

      If k == 0.5, then you need to convert about 15% of your mass into energy. Either you're carrying along a whole bunch of antimatter, or you're picking up mass along the way; no other way to do it. But really, even to get to 0.1c you need one of those two approaches.

      Your k == 0.9 case involves generating kinetic equal to 1.3 times your rest mass to get you up to speed. If we go back to that 2e6 kg shuttle, that means you end up with 2.3e23 J of kinetic energy. Your trip time is about 4.6 years, half of that is 2.3 years. That's average power draw of 3.2e15 Watts while accelerating. Which is 200 times total human power production in 2008...

      Even the k == 0.5 case gives you 25 times total human power production as average power draw. The k == 0.1 case gives 0.8 times total human power production. That's almost starting to look manageable, and only involves a 40-year trip time to Alpha Centauri. :)

    41. Re:Economics by Ihlosi · · Score: 1
      The other way to think of this is that getting up to a speed k*c requires you to completely convert a fraction of your mass equal to "1/sqrt(1-k^2) - 1" to energy.

      That's a interesting point. I haven't thought about this aspect yet.

      Uranium fission converts about 0.1% of the mass each fissioned nucleus into energy, so you can't get to 0.1c using fission if you're carrying along all the fuel.

      That's something spacecraft usually don't do, even today. The shuttles weight at takeoff is about 2000 tons, 1700 of which being fuel. What actually ends up in orbit is the 100-ton shuttle.

      This probably brings us back to the old argument why chemical rockets can't go into space - "you'd need to add more fuel, which requires a bigger rocket, which requires even more fuel, so the thing will always be too heavy or have too little thrust to get into orbit". Turns out that this was mostly an engineering problem (building a rocket motor that provides enough thrust, using a multistage design, etc) and didn't have anything to do with an actual barrier imposed by physics. Who knows, maybe the first spacecraft that goes to AC will be a multistage design, too. At least this saves you from having to do major maintenance to the nuclear reactors - just jettison the thing once it's burnt out and fire the next stage.

    42. Re:Economics by severn2j · · Score: 1

      Sending a Shuttle-sized craft to Alpha Centauri in a matter of years would require roughly the current total energy consumption of humanity.

      Just a thought (and Im not a physicist, so have no idea about the numbers involved), but could we not send something much smaller and lighter, say just a few kilos and the size of a laptop, something that could take pictures and be smart enough to search for planets in the Alpha Centauri system and navigate to them.. Even if it takes 20 or 30 years to get there, the data it sent back would surely be invaluable and would take a lot less time than waiting for some kind of wormhole technology to be invented. Does anyone know if this is possible with our current tech or in the near future?

    43. Re:Economics by tehcyder · · Score: 1

      So in fact peak power draw for your proposed constant-4g trip would be about 10,000,000 times more than the power consumption of all of humanity today

      So, just another engineering rather than scientific problem then.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    44. Re:Economics by BZ · · Score: 1

      The "dump the engine" approach works ok if you don't have to stop on the other end, or if the stopping is cheaper (e.g. moon landing, due to shallower gravity well) than the starting.

      It works for getting out of a gravity well because the whole goal is to get up to speed and stay there.

      But for a trip that involves actually stopping at AC, that won't work; you have to turn over and slow down and that needs as much engine as speeding up.

      Clearly for an AC flyby a multi-stage design would be the way to go.

    45. Re:Economics by Ihlosi · · Score: 1
      But for a trip that involves actually stopping at AC, that won't work; you have to turn over and slow down and that needs as much engine as speeding up.

      Not if you dump half of your spacecraft halfway down the road and have used up more than half of your fuel already.

      Also, I imagine that the reactor doesn't last forever and would need servicing and replacement parts after a couple of years, which is difficult and/or dangerous to do in space.

    46. Re:Economics by BZ · · Score: 1

      > Not if you dump half of your spacecraft halfway down the road and have used up more than
      > half of your fuel already.

      Ah, fair point.

      OK, let's run the numbers a bit more carefully. Say you want to go to Alpha Centauri at 0.5c top speed (so the trip is about 10-15 years). You need to pick up kinetic energy equivalent to 15% of your final mass. Call your final mass M. Assume we're doing fission; uranium fission converts 0.1% of the mass of the fissioning nucleus to energy. Let's assume we fission all our uranium (probably unrealistic) and that we discard the spent fuel continuously so we don't have to cart it around (probably also unrealistic). Minimal amount of fuel is obviously about 150x the final mass of the spacecraft if it's all fissioned at once and doesn't pick up any velocity. But in practice, the amount of fuel depends on your acceleration profile.

      It's not clear to me what an optimal profile is (or rather I'm too lazy to really sit down and crunch the numbers), but if you assume that fuel use per unit time is constant over the duration of the burn (totally not realistic for fission, but so is total fission anyway) then our dE/dt is basically constant. Let original fuel mass be F and final fuel mass be 0. Then initial spaceship mass if F + M. Fuel mass as a function of time if F(1-kt) for some constant k.

      Then dE/dt = kFc^2*0.1%.

      The fraction of energy that goes to our spaceship (as opposed to the remaining fuel) is M/(M+F(1-kt)). So for just the spaceship, dE/dt = kFc^2*0.1%*M/(M+F(1-kt)).

      Integrating, delta E = kFc^2*0.1%*M*(ln(M+F(1-k(delta t))) - ln(M + F))*-1/kF

      Since by assumption (delta t) is such that k(delta t) == 1, this simplifies to:

          delta E = c^2*0.1%*M * (ln(M+F) - ln(M))
                          = c^2*0.1%*M * ln(1+F/M)

      Since we want delta E to be 15%*Mc^2 or so (for speed 0.5c):

          15% = 0.1% * ln(1+F/M)
          150 = ln(1 + F/M)
          F/M = 1.4e65 or so

      That's not a good sign. Not enough mass in the universe to do that.

      If we wanted just 0.1c, then we only need 0.5% instead of 15% of our final mass as energy, which gives F/M = 149 or thereabouts. That's at least physically possible, though we still made some very optimistic assumptions. We do need about 15000 tons of fissile material to accelerate a shuttle-size craft. That's about 1/3 of global yearly uranium production, so not totally ridiculous.

      Different acceleration profiles might give better results that exponential growth of F/M in fractional energy gain, of course. Hard to say for me without crunching the numbers.

    47. Re:Economics by bingoUV · · Score: 1

      So in fact peak power draw for your proposed constant-4g trip would be about 10,000,000 times more than the power consumption of all of humanity today.

      Today is the keyword.

      Let's visit the year 100 AD for a while, so that today = year 100 AD. Energy required by a satellite launch vehicle in year 2010 can be compared to the power consumption of all of humanity today. (This is true since you are only counting fuel/electric energy consumption, and ignoring energy in humans/bulls/horses via food.) But still launching a satellite is possible. Your problem is lack of imagination.

      Further, if you care to visit a 100 million years ago, energy consumption of all of humanity today is zero, since there are no humans today. Yet, here we are, launching satellites, running Google servers, and generally having fun.

      --
      Bingo Dictionary - Pragmatist, n. A myopic idealist.
    48. Re:Economics by BZ · · Score: 1

      > Today is the keyword.

      Sure. The original post in this sub-thread was explicitly talking about the energy consumption today and about the fact that we need to fundamentally change how we do energy generation to reasonably launch a mission to Alpha Centari that will get there in a matter of years. You're saying you think that sometime we'll get there, just like we got from 100AD to today. I'm pretty sure we will too, if we don't do ourselves in first.

      > Your problem is lack of imagination.

      I'm not sure what made you decide I have a problem. All I said is that with current technology, and even then only under the condition that one does not try to gather up interstellar hydrogen, travel to Alpha Centauri in several years elapsed time is not feasible.

  48. Easily Solved by Anonymous Coward · · Score: 0

    With shield technology. Because any civilization capable of constructing ships capable of flying at close to the speed of light will likely have shields that will protect them from interstellar radiation.

  49. Somebody would bloody kill you by SmallFurryCreature · · Score: 1

    They had enough problems already, anybody going to mess with it this time is going home in boxes.

    --

    MMO Quests are like orgasms:

    You may solo them, I prefer them in a group.

  50. Motion is so over-rated. by gestalt_n_pepper · · Score: 1

    Entangle all the matter on the ship and move it .000000009 nanometers. Repeat process really fast until you look like you're exceeding lightspeed and moving. In fact, you'll never be anything but stationary. You get around all those movement problems like those UFOs that seem to act like they have no inertia.

    --
    Please do not read this sig. Thank you.
    1. Re:Motion is so over-rated. by blueg3 · · Score: 1

      I'm not convinced you actually understand how entanglement and quantum teleportation work. :-)

    2. Re:Motion is so over-rated. by gestalt_n_pepper · · Score: 1

      Nor I.

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      Please do not read this sig. Thank you.
    3. Re:Motion is so over-rated. by jgtg32a · · Score: 1

      I have no idea how it works but that just sounds wrong and doesn't even make sense.

    4. Re:Motion is so over-rated. by blueg3 · · Score: 1

      Well, as long as we're on the same page.

      Great username, by the way!

  51. as long as it doesn't prevent by obarthelemy · · Score: 1

    the Improbality Drive, we're all good.

    --
    The Cloud - because you don't care if your apps and data are up in the air.
  52. Yeah but... by JoshuaZ · · Score: 1

    So going 99.9999999% of the speed of light is really bad. Yeah ok. But if you instead go around 90% of the speed of light this won't be an issue. And for most purposes the difference between 90% and 99 isn't that much. The only major issue is that it makes a generation ship design more reasonable since there's less time dilation. But there's no good reason to accelerate much over 90% given the diminishing marginal returns.

    1. Re:Yeah but... by blueg3 · · Score: 1

      There are only diminishing returns for people not on the ship. For the people on the ship, the returns are non-diminishing, due to time dilation.

  53. Same ol' same ol' by Anonymous Coward · · Score: 0

    Remember the times "scientists" claimed it would be deadly to go more than 20mph in a car because the air would get too thin around you and you would suffocate? Good times..

    1. Re:Same ol' same ol' by Geoffrey.landis · · Score: 0

      Remember the times "scientists" claimed it would be deadly to go more than 20mph in a car because the air would get too thin around you and you would suffocate? Good times..

      No, I don't.

      --
      http://www.geoffreylandis.com
    2. Re:Same ol' same ol' by maxwell+demon · · Score: 1

      {{citation needed}}

      --
      The Tao of math: The numbers you can count are not the real numbers.
  54. The Galactic Patrol by UberMunchkin · · Score: 2, Interesting

    Didn't E.E Smith talk about this years ago in the Lensman books. I'm pretty sure the Galactic Patrol moved on tear-drop shaped warships over their original spheres purely because their intertialess drive allowed them to move so fast the the occurrences of interstellar hydrogen atoms began to act on the hulls as friction and slowed them down.

    1. Re:The Galactic Patrol by evanbd · · Score: 1

      At speeds that high, friction doesn't work like you'd expect. Specifically, the gas is sparse enough (and your ship small enough) that the mean free path of the atoms is long; that means you can't establish a bow shock in front that gets the gas out of the way. This actually reduces drag (you interact with less of the gas -- only that portion actually directly in front of you), but means that the drag you do get behaves differently. Each atom hits your ship at full speed, not the reduced (relative) speed that you get in atmosphere after the gas goes through the bow shock. The result is that the gas atoms / molecules don't hit and bounce off; they're going so fast they hit, ionize, chemically react, embed themselves in your hull, and then possibly leak back out much later. In other words, the angle they hit at is irrelevant, and only the frontal area matters.

      (This is all somewhat approximate; it's only mostly true at conditions such as those in low Earth orbit. However, it should be a very good approximation at near-c speeds in the interstellar medium.)

  55. Particle accelerator you say? by Pad-Lok · · Score: 1

    If thats the case, I would'nt mind traveling at light-speed as long I'm provided with a pair of rubber bands and a liquid lunch on the trip. Where do I sign on?

    --

    -- Sauer
  56. So to sum up . . . by base3 · · Score: 1

    FTL FTL.

    --
    One CPU cycle wasted on digital restrictions management is ONE TOO MANY.
  57. Worst job on the ship by Anonymous Coward · · Score: 0

    put a hydrogen-atom-splitter on the bow of the ship, they'll just get cut in half and fall out of the way.

    Imagine the poor SOB that had to crawl out onto the bow with a file to sharpen the atom splitter!

  58. It's the ultimate green energy by Touvan · · Score: 1

    This sounds like power for the warp drive!

  59. my proposition by corbettw · · Score: 2, Interesting

    There's an old saying, nothing focuses the mind like a firing squad. When faced with imminent death, humans are famously adept at coming up with novel solutions to complex problems. To that end, I propose we gather a collection of prominent physicists and place them in a ship capable of accelerating to near-light speed over a period of some years. Put locks on the controls so that they are unable to halt or alter the acceleration, then inform they have X years to come up with a way to avoid being smashed to death by interstellar gasses. Either they come up with a solution and are all saved, or they perish in a fiery ball of glory. Either way, they'll probably all have high schools named after them.

    --
    God invented whiskey so the Irish would not rule the world.
    1. Re:my proposition by jameskojiro · · Score: 1

      Rodney McKay's law of thinking dynamics....

      --
      Tsukasa: All I really want, is to be left alone...
  60. easy solution by hypergreatthing · · Score: 1

    Just emit anti-matter in the front of the ship, annihilate the hydrogen and everything else in the way.

    I'll take my Nobel peace prize now.

  61. you mean theory by mosb1000 · · Score: 1

    According to the theories developed by Tessa Wendel

    There's a little difference between facts and theories. Facts have been tested, theories have not.

    1. Re:you mean theory by osu-neko · · Score: 1

      There's a little difference between facts and theories. Facts have been tested, theories have not.

      Conventional usage is that theories have been tested. If it hasn't been tested, it's not really a theory, it's a hypothesis.

      --
      "Convictions are more dangerous enemies of truth than lies."
    2. Re:you mean theory by mosb1000 · · Score: 1

      From Wikipedia:

      The defining characteristic of a scientific theory is that it makes falsifiable or testable predictions. The relevance and specificity of those predictions determine how potentially useful the theory is. A would-be theory that makes no predictions that can be observed is not a useful theory. Predictions not sufficiently specific to be tested are similarly not useful. In both cases, the term "theory" is hardly applicable.

      In practice a body of descriptions of knowledge is usually only called a theory once it has a minimum empirical basis, according to certain criteria:

      1) It is consistent with pre-existing theory, to the extent the pre-existing theory was experimentally verified, though it will often show pre-existing theory to be wrong in an exact sense.

      2) It is supported by many strands of evidence, rather than a single foundation, ensuring it is probably a good approximation, if not totally correct.

      So a theory does not have to be established by evidence in order to be a theory, it only must make a testable prediction. However, in practice scientists won't call it a theory unless it is established by a body of evidence and largely consistent with existing accepted theories.

  62. Two words by SR-DUB · · Score: 1

    Deflector shield.

    --
    "My God, its full of stars"
  63. Simple solution to simple problems by Anonymous Coward · · Score: 0

    Has any one ever heard of aerodynamics? Make the ship look like a cone and every thing will be deflected. And if the fleet travels in a single line, i.e. drifting, then they can possibly save on nuclear energy as all ships behind the first one wont hit any drag. Just that simple. 100% speed of light achieved!

    1. Re:Simple solution to simple problems by zeropointburn · · Score: 1

      At those speeds, your cone looks more like a flat disk.
      If other ships are behind you, they don't have to deal with stationary interstellar hydrogen. Instead, they have to deal head-on with your exhaust which is carrying substantially more energy. Efficient high-thrust engines also make efficient weapons.
      Beating a dead horse here, but you can't accelerate smoothly to c. The energy required to speed up is itself increasing due to your mass increasing according to your gamma factor. Under modern physics, this has nothing to do with friction*.

      *(There are alternative theories that posit a quantum medium which would cause these lorentz effects as a result of something very like friction. They may even be true, but it is still an entirely separate problem from the interstellar hydrogen friction. Other theories suggest that the property of mass could be modified, in which case you could become massless and be accelerated to exactly c in the process. Then subjective time would stop and you would have no chance of reclaiming your mass at your destination.)

      --
      -1 raving lunatic; +6 subGenius... Things even out...
  64. Paging Dr Bussard by Gothmolly · · Score: 1

    You need that hydrogen to power the spaceship !

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    I want to delete my account but Slashdot doesn't allow it.
  65. I call by the_hellspawn · · Score: 0

    bullshit

    --
    "The laws of science be a harsh mistress." --Bender
  66. Hyperspace by wikes82 · · Score: 1

    It is impossible to reach speed of light, as it will required infinite amount of energy, we are looking in the wrong direction, the solution for space travel is FTL drive capable of opening Hyperspace

  67. Perspective by AlpineR · · Score: 3, Funny

    Do not try to dodge the atoms - that's impossible. Instead, only try to realize the truth: there are no atoms.

    1. Re:Perspective by nomadic · · Score: 1

      I think you're thinking of neutrinos.

  68. Mass Shield - A. C. Clarke by Anonymous Coward · · Score: 0

    In "Songs from Distant Earth", Clarke proposes an interstellar ship with a massive shield of ice (like a mile thick, IIRC) in front of their ship. The story assumed easy ground-to-orbit and infinite energy, so it's science maybe questionable, but sufficiently large ablative shield could be a low-tech solution.

  69. Re:7 teraelectron volts? Meh. by wintercolby · · Score: 1

    7 teraelectron volts isn't even current.

    --
    Most ignorance is vincible ignorance. We don't know because we don't want to know. --Aldous Huxley
  70. Worst analogy ever? by noname444 · · Score: 1

    I'd like to think that most people, like me, have no idea what happens if you stand in front of the beam of the large hadron collider. It might be that nothing happens or you might be vaporized on the spot. From the context I'm guessing more of the latter than the sooner but it's still a crappy analogy. Stick to what people can relate to, like:

    "It's like standing in front of a moving car" or "It's like standing in front of 56 libraries of congress".

    1. Re:Worst analogy ever? by Cunk · · Score: 1

      It would be like standing in front of the Death Star's planet-killing laser. How's that?

      --

      I am the inventor of the hilarious refrigerator alarm.
  71. Aluminum hull.. uh, DUH. by Anonymous Coward · · Score: 0

    "Edelstein "calculates that a 10-centimetre-thick layer of aluminium would absorb less than 1 per cent of the energy", and the intense doses of radiation would damage the ship's structure and fry its electronics."

    Stupid man, thats why they use duranium hull plating with a structural integrity field, and have deflectors!

  72. Re:7 teraelectron volts? Meh. by BadAnalogyGuy · · Score: 1

    They updated it? Where?

  73. Collisions? by nmg196 · · Score: 1

    That problem assumes you actually have to physically travel through all the intermediate space to facilitate faster than light travel. If you just take a slow trip through a wormhole (if they exist) then you might not hit anything at any significant speed.

    Before I get modded down for mentioning something fictious like wormholes in a scientfic argument, bear in mind that faster-than-light travel is also totally ficticious too and most likely will never happen :) You could also argue of course, that if you've gone through a wormhole to facilitate faster than light travel between two places, that you haven't actually travelled faster than light - you've simply taken a shortcut. :)

  74. Improbability Drive by Anonymous Coward · · Score: 0

    Our problem is we are focusing in on velocity, not probability!

    What we really need to do is perfect our modelling systems for the Infinite Improbability Drive, which is powered by Brownian Motion

    Then all you have to do is calculate the exact (im)probability of appearing spontaneously in the destination (everything has a non-zero probability, some just smaller than others), then plug that probability into the Drive, and whammo! The drive generates the requisitite amount of improbability, which thus generates the action desired.

    Oh course, if your math is off you're in trouble. If you get a decimal point wrong, you may cause the ship to turn into a gigantic whale.

    Now if I could just remember the best source for Brownian Motion to use as a fuel...

  75. scientology ftw by archangel9 · · Score: 1

    Didn't L. Ron Hubbard already work this out with the Will-Be Was Engines from Mission Earth? Heller figured out a way to bleed off all the excess energy.

  76. Matters not by Bruha · · Score: 1

    There becomes a speed that our bodies would not survive the tidal forces of nearby gravity fields you may pass through on your journey.

  77. big bang photons may limit cosmic ray speeds by peter303 · · Score: 1

    Cosmic rays appear to have an energy ceiling of around 10^20 electron volts. Thats 10 million times the maximum energy rating of the large hadron collider. This is a proton traveling at almost the speed of light up to eight decimal places. There have been various proposed explanations for this apparent ceiling ranging from inadequate high-energy cosmic ray detectors to no acceleration mechanism known for higher energies. But the most plausible explanation cosmic rays rarely interact with big bang photons or vacuum virtual photons which slows them down. The theoretical numbers tend to agree.

  78. I said this two years ago in a Slashdot comment by InterGuru · · Score: 2, Interesting

    http://science.slashdot.org/comments.pl?sid=177080&cid=14696574

    The density of interstellar space is about one atom per cubic centimeter [hypertextbook.com]. If the spaceship were going near the speed of light (3 x 10^10 cm/sec), it would be hit by 3 x 10^10 relativistic particles per cm^2/sec. This is about the equivalent of one Curie [wikipedia.org] per cm^2, which would kill a human and cripple any electronics on board

    A very heavy magnet could deflect the protons, but the neutral atoms would be unaffected by the magnetic field.

    1. Re:I said this two years ago in a Slashdot comment by damburger · · Score: 1

      Congratulations, just like the author of the story you can now take your position as professor of the motherfucking obvious.

      This is beermat physics. This is beermat physics for first year undergraduates. Why do people have to act like they've just cracked the secrets of the universe simply because they've been told the formula for relativistic energy?

      Oh, and the penetration of protons in aluminium is hardly a state secret, nor are the effects of ionising radiation.

      --
      If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
    2. Re:I said this two years ago in a Slashdot comment by Anonymous Coward · · Score: 0

      I said this two years ago in a Slashdot comment

      Really? Sorry I wasn't paying attention. I'll try and remember this time.

  79. Don't forget by dandart · · Score: 0

    Without our dear inertial dampers, we'd take ages to accelerate to that velocity. Or die whilst being squished into our seats.

  80. Re:7 teraelectron volts? Meh. by wintercolby · · Score: 1

    This revalation seems to be seeing some _resistance_ from the /. community. However, given the number of posts, perhaps it has the _power_ to _electrify_ this community, which often does get the _current_ pun.

    --
    Most ignorance is vincible ignorance. We don't know because we don't want to know. --Aldous Huxley
  81. Are you deef, man? by A+nonymous+Coward · · Score: 1

    One of the changes I have noticed over many years of using English is that the better sounding more poetic words have dropped out of usage. "A well-lit room", "her face lit up" were standard usage. Nowadays everyone says "lighted" and it grates on my ears.

    Same with "spelled" vs "spelt". Sometimes the softer "t" simply sounds better than the harder "d".

    Japanese does this too. "Sa-n" is three, "hyaku" is hundred, but three hundred is "sambyaku" simply because it sounds better and is easier to say.

    I imagine every language does it in one way or another.

    Anyone who pays the slightest attention to harmonious sounds can pick these changes up as a matter of course.

    This can only mean that you are deaf to the pleasures of spoken languages.

    1. Re:Are you deef, man? by camperdave · · Score: 1

      Spoken and written languages are *DIFFERENT* languages. The pen does not make sound, and the tongue leaves no mark on paper. It is easy to translate between them, but each has nuances that the other cannot capture. For example, we signify proper names with capital letters, but the spoken word does not have that capability. The spoken word has tone and emphasis that the written does not capture. So, just because I am not familiar with all of the innuit words for snow, does not mean that I am not familiar with the different kinds of snow they name.

      --
      When our name is on the back of your car, we're behind you all the way!
  82. FAIL by rpresser · · Score: 1

    Star trek: first proposed 1960; first on screen, 1966
    Alcubierre "warp drive" paper: 1994

  83. TSA by WPIDalamar · · Score: 2, Funny

    The real reason interstellar travel will never happen is the time in the security line with TSA would approach infinity for that sort of trip.

  84. You forgot to account for relativity. by microbox · · Score: 4, Informative

    Actually you are missing something very important in your maths: relativity. It doesn't take much shorter to get to the destination from the perspective of someone on earth, but the tale is different for the people on the spaceship. The distance to the destination shrinks.

    Sagan talks about this in Cosmos. If a theoretical spaceship accelerated constantly, it could traverse the entire universe in a mere 50 years -- but by the time it returned earth would be long gone.

    Conceptually -- the universe has no "size" for a photon in a perfect vacuum. From the point of view of this theoretical photon, it is created in a distant star and intersects with your eye instantaneously. From our point of view it could take millions of years.

    Considering that mass is what prevents light-speed travel (as well as the density of the medium being travelled through), that implies an interesting relationship between space-time and the higgs boson.

    The universe is stranger than any fiction.

    --

    Like all pain, suffering is a signal that something isn't right
    1. Re:You forgot to account for relativity. by RobbieCrash · · Score: 1
      Holy shit, this conversation is why I LOVE /.

      Thank you nerds, for making me feel like I belong.

      --
      Keep on knockin'
      https://robbiecrash.me
  85. Take that, sci-fi debunkers! by Tetsujin · · Score: 2, Interesting

    One of those classic complaints against popular sci-fi is that the ships are always pretty and "aerodynamic" (well, mostly, anyway) and that there's no need for this in a vacuum... Well, there you go, one good reason to have aerodynamic space ships. :)

    Making spaceships sleek was a key part of making them fast in the Lensman books for more or less the same reason. (Smith's goofy FTL drive idea negated the mass of the ship, allowing the ship to instantly accelerate to a speed where thrust equaled drag)

    --
    Bow-ties are cool.
    1. Re:Take that, sci-fi debunkers! by roju · · Score: 1

      Shouldn't it be "astrodynamic" for a spaceship?

    2. Re:Take that, sci-fi debunkers! by amorsen · · Score: 1

      Aerodynamic in the Earth sense of the word doesn't matter. You can make the ship any shape you want, all that counts is your cross-section.

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    3. Re:Take that, sci-fi debunkers! by danlock4 · · Score: 1

      Interstellar hydrogen is still a gas... ;)

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  86. The math by Anonymous Coward · · Score: 0

    Traveling at a constant acceleration of g, you will reach the speed (1-2E-8)*c in about 9 years and have traveled 5000 light years.

    Traveling at a constant acceleration, a, you will reach the speed (1-e)*c in about a time c/(2a) * ln(2/e) and have traveled a distance of (c^2/a) sqrt(2/e).

    By the way, speeds closer to c are better not only because you are going faster but because of time dilation. In the above example, you have aged 9 years, but traveled 5000 light years -- it is "as if" you were going faster than light because of the quirky way relativity works.

  87. Really big scoop by dazedNconfuzed · · Score: 1

    Rough calculations...tell me where I'm wrong...

    There's 10^16 m in a light year. There's 1 atom of hydrogen per cm^3, aka 10^-24g/cm^3, aka 10^-18g/m^3. A 1m x 1m x 1-light-year swath of space contains 0.01 grams of hydrogen.

    To gather fuel out of the interstellar medium, you'll need a ram scoop 11.3m diameter just to get 1 gram of hydrogen on a 1 light year journey, or a 357m scoop to get 1kg.

    To parent's observations, you'll have to gather over 6000 tons of matter per light year for his 9600 light year trip, which will require a ramjet scoop 840km wide - just to move 1 ton. Unless I screwed up the math somewhere (probable), you'll have to make a half-million-mile-wide scoop which weighs less than one ton - ain't happening.

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    Can we get a "-1 Wrong" moderation option?
  88. Means it'll work better by Anonymous Coward · · Score: 0

    Just figure out how to harness these 7 teraelectron volts and make the ship go FASTER! You could also feed the hydrogen shockwaves into an alternative fuel tank for lower speed motivation, there-by reducing the amount of fuel you need to carry for non-FTL travel... As an added bonus, this now-motivated hydrogen will increase your mass, and therefore, increase your momentum, so the hydrogen still ahead of the ship would effect the ship even less.

  89. Poul Anderson's Tau Zero by Anonymous Coward · · Score: 0

    Anyone interested in this subject might want to read the science fiction novel Tau Zero by Poul Anderson.

  90. Thanks for pointing this out by sean.peters · · Score: 1

    The slashdot crowd has a tendency to ignore this, but to do a project like this, there has to be some kind of a payoff - and the payoff for an interstellar mission would be 1) uncertain at a best, and 2) wouldn't come for decades or more. The net present value, accordingly, is zero, and the amount of expenditure required would be huge. Therefore, it ain't happening.

    You might make a case that one or more of the world's governments may want to do this for the sheer scientific knowledge to be gained, but still: 1) huge upfront payment, 2) data doesn't come back until we're all dead (I mean, all of us currently alive). It's a really hard sell to your taxpayers.

    So the bottom line here is that interstellar travel is pretty much a non-starter.

  91. The point of the Fermi paradox... by sean.peters · · Score: 2, Insightful

    If you accept as givens that 1) intelligent life develops with relative ease, and 2) interstellar travel is technologically feasible, then what the Fermi paradox is telling you that we shouldn't expect to be the first, as that outcome is quite unlikely. The universe has been in business for almost 15 billion years, which is plenty of time for lots of civilizations to have developed. Since it's manifestly not true that the universe has been overrun with space-faring aliens, one or both of the premises must be false. My personal bet is that they both are, but I'm pessimistic that way.

    1. Re:The point of the Fermi paradox... by Grishnakh · · Score: 1

      There's some bad assumptions here.

      1) that the ETs reproduce geometrically the way humans do. Maybe the ETs have invented birth control, and actually use it unlike humans, and have decided to keep their numbers fixed. Maybe the ETs don't reproduce at all. If the ETs don't have ever-increasing numbers, then they wouldn't need to continuously expand. With interstellar spacefaring technology, they'd be able to terraform worlds with ease, so they might be confined to only a few star systems, perhaps with probes being sent to explore the rest of the galaxy but without the aim of exploitation.

      2) that the ETs are interested in exploring space. Maybe they live on a lush jungle world and live in harmony with their environment, and are perfectly happy to stay there.

    2. Re:The point of the Fermi paradox... by LWATCDR · · Score: 2, Funny

      It was meant to be funny...

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    3. Re:The point of the Fermi paradox... by amorsen · · Score: 1

      There's always the escape of the anthropic principle: Since any colonizing civilization will kill off whatever life was on the planets before, we wouldn't be here to observe the galaxy if we weren't first...

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      Finally! A year of moderation! Ready for 2019?
    4. Re:The point of the Fermi paradox... by jpatters · · Score: 1

      It is quite unlikely that, if extraterrestrial civilizations are common, they would all be like you describe. You could simple add another term to the Drake Equation for the proportion of civilizations that become "enlightened" and thus isolated, and you would still expect, given reasonable assumptions, for the galaxy to be overrun by civilizations that are more like us by now.

      --
      "Remember, there never were pineapple-almond cookies here."
    5. Re:The point of the Fermi paradox... by Ihlosi · · Score: 1
      could simple add another term to the Drake Equation for the proportion of civilizations that become "enlightened"

      Maybe the "enlightenment" consist in figuring out when and how the universe becomes uninhabitable, and concluding that there's basically no point in colonizing like crazy since it'll all be wiped out eventually and inevitably.

    6. Re:The point of the Fermi paradox... by Ihlosi · · Score: 1
      2) that the ETs are interested in exploring space. Maybe they live on a lush jungle world and live in harmony with their environment, and are perfectly happy to stay there.

      Or maybe space travel isn't such a big deal for the ETs anymore, so they can cherry-pick the worlds they colonize. If they're looking for a nice, rocky planet with 1.3g (+/- 0.1g), then our solar system is utterly unappealing to them.

    7. Re:The point of the Fermi paradox... by Grishnakh · · Score: 1

      Exactly. Or maybe they've evolved a higher sense of ethics than humans, and find the idea of conquering other worlds for resources to be abhorrent, and believe that lesser-developed sentient species should be left alone to develop on their own, without interference from more-advanced cultures (aka the Prime Directive).

      Just as we Westerners think of lesser-developed cultures (like those in the Middle East) as barbaric, they probably think of us as barbaric.

    8. Re:The point of the Fermi paradox... by sean.peters · · Score: 1

      Both of those actually seem pretty feasible for at least some populations of hypothetical aliens - so far, we have shown only passing interest in exploring space (mostly because it's really hard) - so we have ourselves as sort of an example of point 2. But surely, at least some would be interested in expanding. It would only take one.

      I still think that the most LIKELY case is some combination of 1) intelligent life is very rare and 2) interstellar travel is (all but) impossible.

    9. Re:The point of the Fermi paradox... by Grishnakh · · Score: 1

      so far, we have shown only passing interest in exploring space (mostly because it's really hard)

      It's also because we're lazy and stupid, and would rather spend our resources on idiotic wars and bailing out poorly-run businesses rather than on learning things.

    10. Re:The point of the Fermi paradox... by Anonymous Coward · · Score: 0

      Too bad what you meant and what happened were not the same :(

  92. How many angels... by sean.peters · · Score: 1

    ... can dance on the head of a pin? Seriously, the difference between 99.9999% and 10% of c isn't that much either, practically speaking. We can't come close to attaining either one. I'll start worrying about these other issues when we develop some practical way to go this fast.

  93. Alcubierre drive by DJRumpy · · Score: 1

    Isn't that what a warp bubble is for?

    http://en.wikipedia.org/wiki/Alcubierre_drive

  94. That sounds like. . . by JSBiff · · Score: 2, Insightful

    That sounds like you're kind of proposing using air resistance to make your car go faster. Which, of course, doesn't make much sense. It's not that the hydrogen has 7 teV of kinetic energy - it's that your SPACESHIP has that energy, and is colliding with hydrogen which is (basically) at rest. You can't extract energy from the 'at rest' hydrogen atoms, because they don't have it. What would happen is that your collision with those molecules would likely destroy your ship (massive hull heating, until you get vaporization; possibly sub-atomic reactions, not sure), and those atoms that passed through the ship would destroy your flesh.

    There is a concept, called the Bussard Ramjet, which suggests using some sort of 'scoop' to gather some of the hydrogen in front of and around the ship, and using some of your kinetic energy to compress/heat the hydrogen until you cause fusion, so that you can actually extract energy from the 'at rest' H, but that is fusion energy, not kinetic energy. Once you've released the fusion energy, you could try to direct it away from the ship, thereby getting a net increase in kinetic energy. But, again, the key point there is the energy is being extracted from Hydrogen fusion.

    1. Re:That sounds like. . . by alpayerturkmen · · Score: 1

      Is it you colliding into the hydrogen atoms, or are the hydrogen atoms colliding into you?

      --
      Alpay Curious...
    2. Re:That sounds like. . . by JSBiff · · Score: 1

      Well, when you hit the gas pedal on your car, is it your car that accellerates inside of the Universe, or is it the universe accellerating around your car?

  95. Meanwhile. . . by JSBiff · · Score: 1

    "it is "as if" you were going faster than light because of the quirky way relativity works."

    Except, in the meantime, time is continuing at it's relentless pace outside of your frame of reference, and when you reach your 5000 lightyear destination, 8000 years (or whatever) have actually passed. As long as you don't care that outside of your 'time bubble', time is quite literally flying by, then, sure, it means you could theoretically travel vast stellar distances 'in your lifetime'.

    There's still the problem that anyone you wanted to rendezvous with has been dead for thousands of years (unless it's an alien with a very long life-span).

  96. Cerenkov radiation by Anonymous Coward · · Score: 0

    Cool.... high energy charged particles zooming through the water in my eyeball make pretty blue Cerenkov bursts.

    As far as standing in the beam goes, it's not that far fetched. Back in the days of 5-20 GeV/c beams at Brookhaven (say in the 70's) there were folks who used to stand looking up the beamline using Cerenkov light in the Mark One Eyeball to "find the beam".

    Besides, somewhere the difference between beam energy and flux has to be reckoned. I mean there are whopping high energy particles hitting the atmosphere with some regularity (see he Pierre Auger Observatory. The flux is low, but the energy makes LHC look like a toy. Maybe the original article covers flux considerations.

  97. Something hardly ever mentioned in these stories.. by Anonymous Coward · · Score: 0

    OK, if one is going to do interstellar travel using conventional means (ie a reaction drive), something that is hardly ever mentioned is, how do you slow down when you get where you want to go? If it's by some kind of rocket, whether chemical or ion beam or whatever, you've got to carry enough reaction mass to turn the darn thing around and brake as much as you accelerated. In my one attempt at writing science fiction, I created something I called draggers. Basically a kind of beltway of objects that ship would hook on to, kind of like a cable car. The dragger would first sling the ship forward, slowing down in the process because it was transferring momentum, but then the ship would pull the dragger forward when it got where it was going, thus transferring the momentum back to the dragger. I confess I didn't think about the problem of the hydrogen. I guess I'd have to have my beltway be a kind of tunnel with a force field to keep out the hydrogen. Like one of those high speed vacuum tube subways some folks have talked about here on earth.

  98. We should build a RETARDUS by zymano · · Score: 0, Offtopic

    Out of a blue police box.

  99. Sometimes by ceoyoyo · · Score: 1

    "Professor William Edelstein of the Johns Hopkins University School of Medicine"

    Sometimes an outsider notices something that everyone in a field really has overlooked, simply because they lack a fresh perspective. More often, the outsider is (a) mistaken, (b) just thinks he's found something worth noting because it's so obvious to everyone else that they don't bother mentioning it or (c) a combination of both.

    This appears to be a case of (c).

    1. Re:Sometimes by Weedhopper · · Score: 1

      Or if you RTFA'd and clicked on the relevant links, you'd quickly discover that the guy is a Harvard trained physicist who happens to be teaching at the Department of Radiology at Hopkins because of his relevant research interests.

      Now who's making presumptions?

    2. Re:Sometimes by ceoyoyo · · Score: 1

      If you dug a little deeper you'd find that W. Edelstein is one of the pioneers of magnetic resonance imaging (my own field). "Physics" is an awfully big field. I couldn't find out what his original specialization was, but it's been a LONG time since he did any space-related work. He is certainly an outsider to the field of manned space travel.

      I've never heard of his co-author, Arthur Edelstein. It looks like he's a programmer at UCSF, formerly UC Berkeley. William's son? Grandson? Google scholar only shows up a couple of hits. W and A Edelstein have a paper on MR in JMRI (looks like from W's lab, he's senior author, A buried in the middle). The two of them have been covering a lot of ground - they've also got an arxiv preprint on electronic voting machines. That's kind of weird too - it doesn't have much to do with physics and every one of the references are web pages, including Wikipedia.

        His abstract seems a bit strange - I'd have thought you'd have to do something a little more in depth to get accepted to an APS meeting. I've seen much the same calculation in Slashdot posts over the years. Maybe those posters should have submitted something. It's also possible there's a lot more content in the actual presentation.

      Now, what was it you were saying about presumptions?

  100. one word: TURBO by newdsfornerds · · Score: 1

    You could use that free electrical power to run the turbocharger! Heh.

    --
    Damping absorbs vibrations. Dampening is caused by moisture.
  101. No, he's a physicist, not a physician by Weedhopper · · Score: 1

    If you click on his name in the article, it takes you to his page, where it's fairly obvious that he's a physicist, not a physician.

  102. SETI by barv · · Score: 1

    Has anybody told SETI yet? This discovery explains why we aren't yet overrun by BEM's.

  103. Am I missing something? by bjorniac · · Score: 1

    So someone does a Lorentz transformation on the denisty of interstellar hydrogen, ramps up the veloicty until he gets the relativistic energy to be that of the LHC and somehow this is news?

  104. Poul Anderson solved all this by Werrismys · · Score: 2, Insightful

    Lasers in front to plasmatize the hydrogen, huge magnetic fields to move the plasma to the REAR of the ship, where a "virtual" burn chamber (really just magnetic fields) captures the plasma. Another mag field keeps the antimatter from touching anything, and gradually releases anti-atoms to the furnace. BOOM mega boost. Easy to shield mere energies if you can do all that trickery with fields. Certainly possible - just very, very hard.

    --
    'Once scientists, even the dim-witted social scientists, get muzzled, the Western Civilization is finished.' - oldhack
  105. MEDICINE ! by Anonymous Coward · · Score: 0

    Since when does Medicine have anything to do with Space Flight

  106. other 'Star/Planetary Systems' not 'Solar Systems' by Anonymous Coward · · Score: 0

    Oh — and the Fermi Paradox applies especially well. Assume that it takes even ten thousand years to colonize a remote solar system, and the entire galaxy would have been overrun by now if a colonizing civilization had started in the terrestrial Jurassic period.

    While we're being picky, there is only one, "Solar System." Uno. It is ours. So named because it's parent star, the sun, is named, "Sol." Unless some other intelligence named their parent star, "Sol," we've got the only one. All other clustered gravitational systems surrounding other stars are either Planetary Systems or Star Systems.

    If you really want to be picky about 'gravitational systems' there are also galaxies and the universe which are all gravitationally related as well, limited by perception and scale.

    Regarding the Fermi Paradox, and I'll be honest I find this just as hard to swallow, maybe, just maybe, we got here first. Someone had to. That's a lonely thought.

  107. Source of blackbody radiation? by marqulo · · Score: 1

    I read (only in one place and cant find that now, so..) that as an object's velocity increases it experiences blackbody radiation in the direction of travel and that the bb temperature of the radiation is related to the velocity. Is this true? And are these sorts of intersteller material particles the cause? What about moving photons through space, as an objects velocity increases it must smack into more of them per time too and with more momentum, no?

  108. Transporter by wooferhound · · Score: 1

    >> planning to go in a biological body? Shame on you,
    >> that will never happen when uploading makes it so much cheaper.

    A Transporter is faster than light isn't it ?
    What is the maximum distance that a transporter will work at ?

    --
    We are Dead Stars looking back Up at the Sky
    1. Re:Transporter by hasdikarlsam · · Score: 1

      A what?

      Let's try not to bring in fictional "evidence", okay?

  109. No time dialation by salemboot · · Score: 1

    No mention of it by Nasa for the Helios probes as it approaches it's fastest speed. http://www.clubconspiracy.com/forum/f30/einstein-vs-tesla-good-article-explaining-573.html toot

  110. not necessarily Physician or physicist by Anonymous Coward · · Score: 0

    Actually, from the article's links, he's a phd working with MRI technology. i.e. he's most likely a physicist, not a physician. Though no doubt he has a certain amount of cross domain knowledge.

  111. an idea by Anonymous Coward · · Score: 0

    Quoting the original article under the link: "As the spaceship reached 99.999998 per cent of the speed of light, "hydrogen atoms would seem to reach a staggering 7 teraelectron volts", which for the crew "would be like standing in front of the Large Hadron Collider beam".

    This is a very bad thing, because humans in the path of this ray would receive a dose of ionising radiation of 10,000 sieverts, and as Bones McCoy would doubtless confirm, the lethal dose is 6 sieverts.

    The result? Death in one second."

    We could use it to execute the deathrow prisoners!

  112. Re:old news... The Lensmen by yellowalienbaby · · Score: 1

    Yeah. I'm pretty sure this was covered years ago in the Lensmen series of books. They dealt with the problem through developing/copying teardrop shapes interstellar craft. In that case though, they termed it as a problem with the friction generated by all the interstellar particles.

    --
    Darwin Hawking Blackmore
  113. The Queen would box your ears by name_already_taken · · Score: 1

    Personal Pet Peeve:

    Americans who butcher the queen's english and then cringe when they hear/see it spoken/written correctly.

    Personal Pet Peeve:

    Brits who aren't aware that American English is actually closer to the way British English was spoken 200 years ago than the current form of British English is now. Are you sure you know who the butchers are? You didn't even capitalize "Queen" or "English".

    While the word "gotten" takes a while to get used to (it's actually correct, but I agree with the way the British dropped the "ten" out of laziness), the spelling simplifications make great sense.

    The "u" has no business being in "color" (it has no function and makes the word look a bit French), and the "o" has no reason to be in words like "fetus" other than to confuse children when they are learning to read. The "o" doesn't modify the "e" sound, so it doesn't belong in there.

    --
    Putting moderation advice in your .sig lowers your karma!
    1. Re:The Queen would box your ears by ceoyoyo · · Score: 1

      Ah, not British. I'm actually from northern Canada where lakes can be froze and groceries can be boughten. We like our extra u though.

      My post was a satire of the post I replied to, which you probably didn't see because it's been moderated into oblivion. If someone wants to say "spelled" that's fine, but "spelt" is NOT cringe worthy.

  114. The Einsteinian DILLEMA by Anonymous Coward · · Score: 0

    As the speed of the ship INCREASES its MASS INCREASES, therefore DOES NOT THE POWER AND EFFICIENCY OF THE FUEL OF THE SHIP AND ITS ENGINES ALSO INCREASE ... ... therefore, GOD WAAAAAASSS the BIG BANG and the first consciousness to approach the speed of light in a ship, (It quickly accelerated to maximum density and then exploded creating the universe sized time rift which now we are all trapped in !?!?!?!?!?!

  115. Interstellar Hydrogen Prevents Light-Speed Travel? by John+Hasler · · Score: 1

    No. Special Relativity prevents light-speed travel.

    --
    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
  116. At reasonable speeds (such as .99c)... by John+Hasler · · Score: 1

    ...A thick block of tungsten will do as a shield (it'll get red hot). Make your ship long and skinny to minimize weight. Note that there is no point in any sort of aerodynamic shaping.

    --
    Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
  117. Tax dollars at work by AmericanInKiev · · Score: 1

    Good to see where our tax dollars are going. Where would this country be if we didn't rule out speed of light travel?

  118. Use a mag scoop aka Bussard ramjet. by Criton · · Score: 1

    Just use a magnetic scoop sorta a VASIMR engine in reverse and scoop up the hydrogen atoms and concentrate them. They'll under go fusion and you get some extra thrust