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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."'"
They already figured this out nearly a hundred years ago.
That's what the deflector array is for.
Don't take life so seriously. No one makes it out alive.
And I was just about to get into my 99.999998% lightspeed spaceship.
After reading the article (yeah, I know...) tow thought spring to mind...
/., I expect you all to forgive me for using the present tense here [grin]
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
Physicists get Hadrons!
I go back into the past ?
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."
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
put a hydrogen-atom-splitter on the bow of the ship, they'll just get cut in half and fall out of the way.
"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!
Free Martian Whores!
Guess we'll just have to go at 99.999997% of the speed of light then.
If you want to travel light speeds, you have to convert yourself into light first.
. . .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. . . .
"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?
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.
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
All you have to do is navigate around the hydrogen atoms.
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
What the hell was that? They've gone to plaid!
If it isn't broke, tinker with it till it is!
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
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.
I'll bet that would sting.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
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
HAH Noobs thats what the NAVIGATION SHI... aww damnit.
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"
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
How about a giant windshield wiper wiping slightly faster than the speed of light? amirite? amirite?
"To err is human, to mod Funny divine."
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.
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.
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?"
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.
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
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.
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.
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.
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?
What does this guy know about space travel? He's a prof at a medical school, FFS. This is rocket science, not brain surgery!
We don't need 99.99999% of the speed of light. We need FTL (Faster Than Light), for before 2012 please !
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.
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.
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.
the Improbality Drive, we're all good.
The Cloud - because you don't care if your apps and data are up in the air.
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.
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.
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
FTL FTL.
One CPU cycle wasted on digital restrictions management is ONE TOO MANY.
This sounds like power for the warp drive!
http://www.unfocus.com/
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.
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.
There's a little difference between facts and theories. Facts have been tested, theories have not.
Deflector shield.
"My God, its full of stars"
{{citation needed}}
The Tao of math: The numbers you can count are not the real numbers.
You need that hydrogen to power the spaceship !
I want to delete my account but Slashdot doesn't allow it.
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
Do not try to dodge the atoms - that's impossible. Instead, only try to realize the truth: there are no atoms.
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
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".
They updated it? Where?
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. :)
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.
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.
There becomes a speed that our bodies would not survive the tidal forces of nearby gravity fields you may pass through on your journey.
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.
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.
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
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.
Infuriate left and right
Star trek: first proposed 1960; first on screen, 1966
Alcubierre "warp drive" paper: 1994
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.
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
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.
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.
Can we get a "-1 Wrong" moderation option?
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.
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.
... 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.
Isn't that what a warp bubble is for?
http://en.wikipedia.org/wiki/Alcubierre_drive
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.
"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).
"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).
You could use that free electrical power to run the turbocharger! Heh.
Damping absorbs vibrations. Dampening is caused by moisture.
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.
Has anybody told SETI yet? This discovery explains why we aren't yet overrun by BEM's.
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?
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
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?
>> 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
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
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
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
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...
No. Special Relativity prevents light-speed travel.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
...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.
Good to see where our tax dollars are going. Where would this country be if we didn't rule out speed of light travel?
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