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Wormholes Unstable (BBC)
An anonymous reader writes that "The BBC reports on recent theoretical physics research showing that wormholes may not be very useful for space or time travel. Wormholes with smooth or classical spacetimes appear to be unstable and fall apart quickly. Too bad for budding time travelers and space explorers!"
who read the headline as "Windows Unstable" and thought, duh... of course it is...
Duh, that's why they have the dampener things on the stargate.
And they only take reservations millennia in advance. I hate to cancel now.
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A completely theoretical and as-yet-to-be-discovered phenominon is unstable, and unusable for transportation? Say it aint so!
This work obviously needs to be run by a futurologist for a second opinion.
I'll turn into a supernova and burn up everything. Well I'll turn into a black little hole and you'll turn into string.
According to the article theoretically a wormhole that opens to a random place/time is still stable. It would make a great getaway. "You don't know where I'm going and neither do I. *poof*"
That's why the artificially-created stable one near the Deep Space Nine station was so strategically valuable.
Elementary sci-fi!
One line blog. I hear that they're called Twitters now.
Well there goes my plans for the summer!
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
wormholes? all bill and ted needed was a phonebox.
I suppose this makes it more like the "improbability" drive now, doesn't it?
You wouldn't have to be in a wormhole very long to travel somewhere (sometime) else--as long as you're not counting on the return trip.
I might know what I'm talkin' about, but then again, this is Slashdot...
Maybe one day you'll get the chance to go back and time and try again.
We all knew from DS9 that stable wormholes just don't happen in nature. That's why the one to the Dominion Empire was so unusual. It was STABLE. Very rare indeed, and it needed the intervention of an alien species to stay intact.
Why is this considered news?
"Live Free or Die." Don't like it? Then keep out of the USA
I was under the impression this was already established. I remember seeing a TV show about Stephen Hawking and some other guy betting that time travel was impossible due to the instability of wormholes.
We all know that there's only one stable wormhole in the galaxy, near a planet called "Bejor."
- It's not the Macs I hate. It's Digg users. -
"I felt a disturbance in the force. It was as if millions of sci-fi fan boys suddenly lost their erections and started crying."
Even though I'm a huge SG1 fan, I (and a lot of others in my Information Theory class) had a _lot_ of trouble with the wormhole concept. I don't know enough physics to articulate my problems well, but I really can't imagine how the entropy associated with these things would allow any _useful_ information (leave alone objects) to pass through. Any physics-literate /.-ers care to comment?
Go somewhere random
I thought the idea was to use some exotic form of energy to hold them open.
Technoli
or you'll end up in the Delta Quadrant.
That they made jodie foster wear that goofy outfit when she travelled through the wormhole.. come on, I'd like to think todays audiences are mature enough to handle a little bit of nudity, seeing her hotly oiled up and sleek body slips through the cosmic threshold shouldn't dismay anyone.
I'm going with her on the next trip, in the raw baby!
"Honey, call the space-time travel agent - we have to take the train to Andromeda or risk being thrown into separate tangential universes and stuff. "
We can send a man to the moon, but we can't even get a wormhole to stick around.
Raise your children as if you were teaching them to raise your grandchildren, because you are.
Well, no wonder the time-travel convention was a bust :)
And that just seems so shortsighted...
From the article:
But building a wormhole with a throat radius big enough to just fit a proton would require fine-tuning to within one part in 10 to the power of 30. A human-sized wormhole would require fine-tuning to within one part in 10 to the power of 60.
"Frankly no engineer is going to be able to do that," said the York researcher.
Well, I don't know if any engineer could do that with pencil and paper, but I am sure a computer could do it. Well, I am not sure a computer could do it, but growths in computational speed and power have certainly surprised us so far...
Hopefully I didn't put any [] around my words.
Just apply a charge to a conductive body. The charge will dissipate across the entire surface of the body. Without the ability to channel or control electricity it will never be useful.
It's Heisenberg all over again!
Man, if only we had known that wormholes were unsafe for space travel back in 1995, we could have been spared the agony of seven seasons of Star Trek: Voyager
JANEWAY: Chakotay, take us into the wormhole.
CHAKOTY: Aye aye, Captain!
PARIS: (aside to TORRES) Heh, she said "wormhole."
*crunch*
The one I was using tomorrow worked just fine, well, it did until it broke yesterday.
----
Everyone knows you have to move out of any nearby gravity wells before you can initiate a jump.
Hokey statistics and ancient misconceptions are no match for a good thought in your head, kid!
Ok, so a semi-classic wormhole is unstable....
Does it fall apart in pico seconds, seconds, days, weeks, months, years, eons??
Depending on how hard they are to make (assuming you can make them) perhads it is GOOD that they fall apart in a few seconds. That lets you warp a ship out of the system without upsetting all the orbits etc.
Wormholes with smooth or classical spacetimes appear to be unstable and fall apart quickly.
Mathematically, physics says the same thing about a stable fixed-point in a static magnetic field.
And yet...
I have one of those cool little-magnet-levitating-over-a-big-magnet toys sitting on my desk at home, happily violating the (human-formalized) laws of physics.
Funny how, despite the numbers just not working well, little things like "friction" in the real world make sooooo many "impossible" things work just fine... All those nasty infinite series that would otherwise make the world very messy to calculate, eventually taper off to nothing, in a very real and practical way.
So how long before they start mining PHB's brains for Exotic matter?
If brevity is the soul of wit, then how does one explain Twitter?
If wormholes allow time travel, their brevity is nearly irrelevant.
--
make install -not war
(Well, it's not really new anymore, but ...)
* Garbage disposal, including of Objects of Power of the sort that seemingly vanquished evil galactic overlords require for their return to total mastery.
* Practical jokes. "Star? Your planet orbited a star? I don't see a star around here, do you?"
* Sex toys for transcended superbeings who exist as fluctuations in the quantum foam but who have not forgotten what it was like to be carbon based, young, and in estrous on the sunny plains of Ghyr'd'tos.
As Hawking, and several other authors are quick to point out, as we don't yet have a unified field theory, nothing can be ruled out completely, it may be unlikely, but nothing is impossible...yet.
but I have wormhole technology implanted in my brain.
"travel through wormholes ain't like dusting crops farmboy!"
It's fiction. Going nowhere doesn't make as interesting stories as going somewhere.
Why is this a bad thing? It is only bad if your goal is to return to earth in an A to B... B to A fashion. In 200-1000 years we may be very interested in simply jumping in a wormhole and seeing where it takes us. It still could be great for SPACE EXPLORATION.
...we fired a beam of concentrated verteron particles to help stablize the nutrino field, then use the warp field generated by the nacelles to bind the fabric of space-time while travelling through the event horizon?
*g33kd*
Fools.
BDR Gear
Outdoor gear, MREs, and more!
Not only does it let you travel in style, but the stainless steel construction makes it ideal.
You are who you are, let no one tell you different. But, never close your mind to a new point of view.
I fear there are bigger reasons why people won't be traveling through wormholes. First, biologically tissues are far too fragile for the intense gravitational, electromagnetic and radiation fields that are likely to come with these phenomena. Second, biologically systems (and the attendant life support systems) are far too bulky. Creating a wormhole is uniform over the size of a person or ship will be extremely difficult. Even if the hole is big enough for a person, the center of the wormhole will likely stretch space in ways severely different from the edges of the hole. Macroscopic objects would be shredded.
Two wrongs don't make a right, but three lefts do.
Not a single John Crichton commment...Just a bunch of DS9/SG1 tripe -_- Where are the REAL nerds at!
Speaking of wormholes, there appears to be one in Slashcode that is making comments disappear from one thread and have them appear in another, possibly in a completely different article.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Enormous energies to open... check.
Enormous energies to keep open... check.
Enormous external energies trying to shut it... check.
Instability... check.
Yup, every single thing about wormholes said so far in the pop-sci world looks to be largely a lot of the same. Big energy to make it work, and then it doesn't for very long. Did the BBC report just summarize what's already been written by Kaku, Pournelle, etc., etc., etc., ad nauseam?
I think we have another instance of a not-so-new formula for getting something on Slashdot: collect what's already gone before, write the same conclusion in new words and sentences, put a new author's name on it, proclaim it sensationally.
I'm waiting for the reports on whether wormholes can even be used for transport regarding effects on space-time geometery and how that relates to basic particle stability, ie, can the conditions in and around wormholes cause proton decay, or undo weak or strong nuclear forces? We have no idea what would happen to matter going into any wormhole that would actually be possible as opposed to ideal cases on paper. What we use for conjecture on paper bears little relationship to the real physical world frequently. What if we're totally wrong about quantum electrodynamics inside a wormhole?
If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
...and they've implanted the knowledge in the brain of one "John Crichton"
Buzzing the information Superhighway at Warp speed
let me go back and make sure this report never comes out...
Well John Titor did it so obvisually it can be done.
Anybody who watched Farscape knows that already! But tell these guys to ask John Chrichton, as he's figured it all out...
No wonder my travel agent doesn't offer an insurance policy with a death benefit for wormhole traveling. I guess taking a black hole would be safer.
my bad
If this had come out earlier, a lot of nerds wouldn't have wasted a perfectly good Saturday evening. http://web.mit.edu/adorai/timetraveler/
From the summary:
:(
"Too bad for budding time travelers and space explorers!"
You tell me, now I'm stranded in this time!
(I miss my XBOX-3D *sniff* )
Wormholes entirely governed by the laws of quantum mechanics, on the other hand, would likely transport their payloads to an undesired time and place. And with the right source of brownian motion, you could make your host's undergarments jump an entire foot to the left.
io hymen hymnaee io
io hymen hymnaee
Worms might have conquered the universe except for a fatal flaw. They can make stable wormholes but can't stay underground after it rains.
The world is made by those who show up for the job.
This would never, ever happen naturally, but nowadays most people have a silicon chip strapped to their wrist. See if you can count how many are within five feet of you.
If wormholes are possible at all, then we'll just have to build a control system to stabilize them, that's all.
PHEM - party like it's 1997-2003!
too bad he's unaccounted for.
From the article:
:)
"The concept of wormholes will be familiar to anyone who has watched the TV programmes Farscape, Stargate SG1 and Star Trek: Deep Space Nine.
The opening sequence of the BBC's new Doctor Who series..."
Why didn't they just post the article directly to slashdot?
-j.
Apparently everyone at slashdot thinks this is funny. Isn't this supposed to be BAD NEWS?
I thought that all earlier calculations on wormholes showed that you needed something exotic to keep them from collapsing.
The wormhole doesn't have to be stable to be useful. You could create a wormhole around a ship, and allow it to break apart behind. You could also say that rockets are unstable, because they only have a stable stream of plasma for a few feet--yet they still move the rocket.
Of course, putting limits on things that are still fiction is kind of ironic.
>>"ad space available -- low rates!!!"
Check it out! http://www.nytimes.com/2005/05/23/business/mutfund /23cnd-bbc.html
Answer: we don't really know to travel into the past (although there are some guesses, mainly involving wormholes). AFAIK, there is nothing in relativity or quantum mechanics that explicitly prevents you from time traveling (and there are some possible ways to). You've hit upon a real problem, though.
One season of Farscape could have told them this.
Not to mention pale skinned chicks are hot and there are creepy dudes in leather trying to get wormholes for themselves......
You need to have a net negative mass, which means that your exotic matter (or energy equiv) must be equal to the mass of the object traversing the wormhole, PLUS the mass of the wormhole itself, PLUS the mass of any other particles within the wormhole, PLUS the mass equiv of the energy that the vaccuum created naturally has.
You also need to bear in mind that exotic matter is believed to have a very short half-life - about 10^-30 seconds - which means that it must be traversing the wormhole at high speed and must constantly be replaced at that rate.
But that isn't all! There is a problem with wormholes in close proximity to each other - they are unstable. And quantum-scale wormholes supposedly occur everywhere in the quantum vaccuum. So, you've got to do some fairly complex stuff to exclude other wormholes from the vicinity of the one you want.
Generating the exotic matter/energy is also a hard problem. Methods include the Casmir Effect, which requires generating fields of absolutely staggering strength to exclude all possible positive energy between two plates. The exclusion principle, combined with the requirement that a vaccuum must have a non-zero state in QM, is what forces the existance of a negative state.
So, what you need to do is basically have gigantic Casmir Effect-based exotic matter generators, which will require vastly more positive energy then the negative energy they create.
I think I figured out that you'd need to convert most of the galaxy into pure energy in order to move even a relatively small object via a wormhole over any kind of reasonable distance, once you take these additional requirements into account.
The problem is, if you are capable of collecting a galaxy together to convert it into enough energy to do this, you have sufficient technology to reach anywhere in the galaxy anyway, making the wormhole method of travel totally unnecessary. Besides which, you also get the benefit of having somewhere to go.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Okay, apparently exotic matter doesn't work, according to the article. /lart self. It's interesting that the uncertainty principle can work on wormholes also...
of course, 10^-18 is a number very similar to 10^60 or even 10^-60.
Or not - bad comparison.
Well, that's one way to get a stable wormhole.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
here we come!!!!
Privacy is terrorism.
That aliens really did kidnap humans for genetic experiements. God damn those Eidolons.
Come on you people, this is like having a topic called "hacker used unix!", or "bill gates uses microsoft windows!"
"If you loved me, you`d all kill yourselves today"
Spider Jerusalem
There's time travel, and then there's time travel.
If you travel more than a light year in less than a year, you've made a "time-like" journey. Theories about wormholes mostly permit this. That implies some strange causality, but not nearly as strange as what's ordinarily thought of as time travel. You still can't send yourself a signal "from the future", or affect your own past, even with multiple hops. From the point of view of your distant destination, you've traveled backwards in time, but not from your own point of view (well, you can watch your own past in real-time by "getting ahead of the light", but that doesn't lead to paradoxes by itself).
Even this kind of wormhole would present all sorts of difficulties, however. If the wormhole was "timelike" and the mouths were close to one another, it's quite possible for a photon to get caught in a loop, multiplying endlessly until the energy collapsed the wormhole. It's hard to see how this could be avoided for neutrinos.
Socialism: a lie told by totalitarians and believed by fools.
Wormholes with smooth or classical spacetimes appear to be unstable and fall apart quickly.
That's when you inverse the warp field to produce a reverse graviton stream, thus stabilizing the worm hole to maintain continuous fabric in space-time. Everybody knows that. Don't you watch Star Trek?
I've been taught that Einstein-Rosen bridges ("Wormholes") are unstable in MSc lectures. This knowledge is at least five to ten years old. I can't find the appropriate paper at the moment, but if you try this summary of Black Hole Theory, for example, it will tell you on page 25 that Wormholes are not crossable. There are similar problems with time machines ("closed timelike curves") and other strange phenomena of Quantum Cosmology: They all sound so cool at the beginning, but the closer you look, the less interesting they get.
You can RTFA, or read the actual paper here. (available as PS or PDF). Beware, a working understanding of general relativity may be required.
You never watched Deep Space Nine, did you? You lucky bastard!
Not Buzzword 2.0 compliant. Please speak english.
Not only are they unstable, but they're way too small to travel through. But they are a nice place for the worms to live.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
That would make a bit of sense.
I think we've pushed this "anyone can grow up to be president" thing too far.
*:Must be read in an "over the top" scottish accent!!:*
Captain! The crew is ready to travel through uranus, there is just one problem, the wormhole is not quite as stable as we thought... we're gonna have to astroglide it before we can fire off the probability drive and then we can go through the black hole and be givin' her all she's got!!
But I've had a sneaky ugly worry (founded by far too little knowledge of anything resembling necessary science) that it could conceivably be a quantum phenomenon, in other words no other species could exist within our light cone (or galaxy? farther?) due to some universal law that makes it impossible. Though anthropomorphic law aside, that would make it really, really unlikely that we exist, statistically speaking. Anyway, much as I would really like to see some FTL, and assuming the quantum worry I have is unfounded, there are two good things that could come out of this opinion that wormholes are unstable. For one thing, as much as I try to explain SETI etc. to my Dad, he says "I don't want to have any bug eyed monsters coming here" and of course, if they are like those in Starship Troopers then he's right. We're safely far away for a while maybe. Other thing is, no wormholes might mean that there is a chance of life existing outside our "light cone", i.e. the farthest we could ever go in the universe at light speed, I suppose. Those reasons both make me feel a little better. Any physicists out there?
What if you made the wormhole about 2 feet long?
Then factor in, that the exotic matter is accelerated to give it more mass.
Now add that the object being moved, is considered stationary, as it is moving in a "bubble" inside the wormhole.
Look at bubbles floating to the surface in water. How could something a thousand times less dense than the staggeringly massive ocean hope to push it aside?
Is there some rule that a wormhole must reach from the thing being transported to the destination? Can't it be created (like the even horizon of a bubble) along the way.
What is the calculation for the energy for a worm-bubble? How much acceleration of the exotic matter is possible?
By the way, I'd like this point I'm making considered as prior art in case Microsoft copyrights.
>>"ad space available -- low rates!!!"
It depends on what quickly means here.
I can tell you that this article is completely false. Why, I just got back from Alpha Centauri not 5 years from now through this very technology!
No smoking sigs indoors.
It is great how there is this heated discussion about whether wormholes are or are not safe for space travel (and people are actually disappointed when they turn out to be unsafe) while no-one has ever seen a wormhole to begin with.
With gas costing what it does this is how I was planning on wormholes to get me to Cancun Mexico this summer. Time rethink my summer plans.
shame on you for not noticing the farscape reference here:
2 &cid=12615641
http://science.slashdot.org/comments.pl?sid=15046
what kindof fan are you? Only a new seasoner???
Gravity Sucks
Also a late arrival, came after your comment:
2 &cid=12615816
http://science.slashdot.org/comments.pl?sid=15046
Gravity Sucks
The BBC reports on recent theoretical physics research showing that wormholes may not be very useful for space or time travel. Wormholes with smooth or classical spacetimes appear to be unstable and fall apart quickly. Too bad for budding time travelers and space explorers!
"Also in the news this evening, recent theoretical physics research suggests that the Earth's atmosphere will never be very useful for traveling long distances over the surface of the planet at great speed. Air appears to be unstable, and any machine we make to try and utilize this medium for human flight has always fallen apart quickly. Too bad for budding air travelers and aviators. Time to give up now."
The universe will always be bigger and more complex than we think it is, folks. I wouldn't worry too much about never being able to time travel, use wormholes or travel faster than light (or all of the above). Eventually a way will be found, even if it means breaking the theoretical laws we think we know. Any scientist worth his or her salt knows that no matter how much we learn, there may always be something around the corner that will blast what we thought we knew into a million pieces and turn everything on its head. It is the height of hubris to assume otherwise.
This isn't exactly a response to your post, but more a question for this entire thread... but you seem like you may be a physicist or at least well versed enough in the mathematics thereof to be able to do "back-of-the-envelope calculations" about it, so maybe you can answer this question for me.
Why is it assumed that because something has negative mass - which I would define as "the quality of being repelled from, rather than attracted to, ordinary positive mass" - it has negative *energy*? Likewise, why is it assumed that any energy (such as vacuum energy) translates directly into positive mass?
I've always viewed it similarly to charge. Both mass and charge are a form of potential energy. An electron and a proton have the same amount of electrical potential energy as one another, only differing in the nature of that potential relative to other charges (whether it repels or attracts a positive or negative charge). But does a proton then have "positive" potential energy and an electron have "negative" potential energy? If the answer to that is no, then why does something with "negative" mass have to have "negative" energy? Is a space filled with a negative charge "less than empty vacuum"?
I'm well aware of e=mc^2 of course, and why that would lead to a negative value for e if you have a negative value for m. But given that physics traditionally deals with only positive values for m, wouldn't e=|m|c^2 (using the absolute value of m, instead of just m) return the same results for all physics thus far, dealing with positive mass, without the counterintuitive "less than nothing" idea of "negative energy" if ever we managed to produce something with negative mass?
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
anyone who's watched farscape already knows this...
I work for the Department of Redundancy Department.
"Wormholes with smooth or classical spacetimes appear to be unstable and fall apart quickly."
Could this be a clue that wormholes are only stable as long as their "perfection" is altered/modulated by data being transferred by some method, so that they are in a constant state of change? Just a thought that occurred to me, I'm not a cosmologist or physicist, etc.
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
How interesting that this was reported just two days after I completed my famed Damn Wormholes! bumperstickers. Buy many as they are now unstable and may disappear or explode at any minute.
Fully licensed blockchain psychiatrist
actually I think you can.
here is a page explaining how sending messages to your own past is possible, provided you have a few friends and a method of sending messages instantly, but it really works the same way with any message sent faster than light.
If you can transport matter faster than light, then you can do the same and send for example yourself back to your own past.
I do not think there is a way around that if you have faster-than-light or timelike journeys
Things would start changing from the moment you get the message around you since you would do things differently than if you had never received the message. So really the lottery type thing would only work if the numbers were picked before your 'ripples' in time made it to them. An example of this is in the first (I think) episode of 7 Days at the end, he bets all his money on a basketball game where the team one at the last minute where the ball just barely made it in (it was on the rim and fell in), except him going back changed it so that team ended up losing and he lost all his money.
I've always wondered though, where does his self in the past go when he travels back in time? Also it would cause a grandfather paradox (him traveling back in time would prevent the need for him traveling back in time, so he would of never traveled back in time, and......)
What if you built your wormhole, set the two ends 10 meters apart on Earth, then sent one end far away under extreme acceleration and back to Earth again, so that the end you sent away is "younger" than the stationary end, and has (from the perspective of anyone traveling with the sent-away end) raced, say, a hundred years into the future in a (subjective) decade.
Looking back through the sent-away end (if it could function like just some sort of window), did the travelers see time on Earth near the stationary end pass at the same rate as them, i.e. on the other side of the wormhole, as viewed from the sent-away end, only a decade has passed? If that is the case, then couldn't they just step through the wormhole when it gets back to Earth, and come out 10 meters away and 90 years in the past? If people 300 years after the sent-away end returned, stepped through the sent-away end back 10 meters and 90 years, then walked 10 meters over to the sent-away end again, could they not do this three times and go back 270 years? (At which point the local-time sent-away end is far out in space and not available to be stepped into again).
Basically, with such a construction you could always come back in time to the creation of the wormhole, jumping back in increments of whatever the age difference due to relativistic effects is. And with that ability, you get all your staples of temporal paradoxes possible. If next year we build this thing, the sent-away end returns in 110 years with a 100 year differential, and then one of my psycho descendants 200 years from now jumps back twice and kills me before I have any kids... there's your grandfather paradox.
Although there is the alternate possibility which would disallow this... those who travelled with the sent-away end, looking back, saw time on Earth pass by at an accelerated rate, everything running fast-forward (faster as they on the ship accelerate more), likely blue-shifted, extra bright/hot, probably a pressure differential due to relative temperature differences (if both ends are in atmosphere)... in effect, the people on the ship looking back see everything speed up and all forces amplified, so time runs fast-forward and light and heat explode out of the wormhole; while those on Earth looking through the wormhole at those on the ship see everything slow down, forces diminish, things cool off, lights darken and redshift, as air is sucked through the wormhole into the ship.
When the ship returns to Earth and becomes stationary relative to the other end of the wormhole, the effects normalize, but to both the people on Earth and the people on the ship, 100 years worth of events have passed on Earth, and 10 years of events have passed on the ship. But to the people on Earth, those ten years on the ship stretched out slowly over 100 years of viewing time, and to those on the ship, those 100 years on Earth exploded past in a decade. The wormhole ends stay synched in the same timeframe, not permitting time travel that way, and offering the interesting prospect of viewing relativity at play.
I'm not sure myself which is the correct scenario. Any physicists care to comment?
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
AFAIK (and that's not much) energy is something needed to "have potential", or ,in other words, to do work.
Moving something is a kind of work.
How do I move the entire fabric of space with some "exotic matter" that has energy in debt?
Also, if I am unable to measure the amount of energy or potential that I have (or that any other thing has), how do I recognize something that has negative energy?
I see connected people! - The seventh sense
The same applies for women.
In other news, scientists speculate the sun might be hot.
I don't need to travel in time, I just need to transmit winning lotto numbers to myself.
Don't worry, it can be stabilized with a concentrated tachyon particle stream from the main deflector dish. Everyone knows that. ...Oh you might need to reroute power from the aft shields but that's fine.
If humans are ever to figure out how to travel through time, wouldn't someone have done it already? Unless there's going to be a totalitarian government keeping track of our every actions, if some genius whackjob wanted to come to sometime before now, he or she could.
All the points raised in the article were discussed in Robert L. Forward's Indistinguishable From Magic, which I read back in '95. And it's not like he came up with these ideas... his book is just a paperback.
One thing Dr. Forward talked about in his book was using micro-wormholes to send radio transmissions. Sure, it's not as cool as sending a ship through, and anyone who received the message couldn't send one back to us via the same wormhole, but maybe someone on the other end of the wormhole might have a few trick up their sleeves to let us know they received our transmission.
PS - this is my first post on Slashdot
The bits on the bus go on and off... on and off... on and off...
I just completed a podcast interviewing Dr. Stephen Hsu, one of the contributors to this research. He explains more about how wormholes are theoretically impossible to keep stable.
Publisher, Universe Today - http://www.universetoday.com
I was just looking, but yours appears to be the only. So here goes:
Dren! I'll never get back to my frelling home then.
Musicians don't die. They just decompose.
He was droped into warmhole. How we can save him?
The same article says that squeezing a proton through needs ~10^30. An electron is three orders of magnitude smaller, so now we're at 10^27. Photons can have even less energy. Still a ways to go, but in the 1940's it would have been considered utterly impossible to get silicon as pure as we have now, by nearly as many orders of magnitude.
Maybe we won't ever be able to squeeze a human through. You're saying you can't see any use for a 'time modem'?
PHEM - party like it's 1997-2003!
I recall reading about doing this - acceleration raises the energy or 'temperature' of a vacuum (it creates particles with energy) analogous to how compressing a gas raises its temperature, and likewise, stopping acceleration lowers the energy just as releasing the pressure on a gas lowers its temperature.
If you have a box with a vacuum (temperature at absolute zero) in it, then accelerate it, creating energy inside, and allow the energy to dissipate (so the temperature is again at absolute zero), then remove the acceleration, the box will have negative energy in it.
This is more of a thought experiment than something that can easily be done. Googling "zero point energy" should give more info/a better explanation, though it looks like there's some crap ("devoted to the new energy technology") out there too.
Tag lost or not installed.
In AB's frame of reference the spaceship is longer than the station, so B has to pass D before A passes C.However, in CD's frame of reference, the station is longer than the ship, and therefore A has to pass D after A passes C.It is impossible to arrange events such that, in both frames of reference A is adjacent to C "at the same time" that B is adjacent to D. The example you cited makes sense given our Newtonian intuitions, but is not actually possible.
Socialism: a lie told by totalitarians and believed by fools.
hmm...
Let's see wheter this makes sense:
First, neither of the participants (me, Alice, Bob, Carol or A,B,C,D in your example) has to move at a very fast speed.
Provided we have a way to send messages to each other instantly (or arbitrary close to instantly), it should work with me and Alice standing somewhere, and Bob and Carol walking in the same direction as each other.
Second, to avoid any complications with adjacency (I hope), lets say that next to me are a million Bob clones in a row, walking past me one at a time, in the general direction of Alice, and next to Alice are a million Carol clones walking past her in the same direction.
- I send an 'instant' message to Alice.
- Alice gives it to the next Carol clone, as soon as she gets it.
- Carol sends it instantly to every Bob clone.
- the next Bob clone to pass me after receiving the message gives it to me.
Because the frame of reference of the clones is not the same as my and alice's frame of reference, the message should arrive slightly bevore I sent it.
It seems to me that this way no assumption about the order of events is neccessary. No matter in which order the other participants perceive the events, as long as they forward the message as soon as they receive it, it will get to me before I sent it.
You still have a problem even in the "multiple Bobs" example, it's just harder to illustrate. From Carol's (and Bob's) point of view, Bob receives the message at the same time Carol sends it. Carol and Bob can synchronize clocks, and mark the time the message was transferred, and agree it was instantaneous. So far so good.
However, from your point of view (and Alice's), the message arrives at Bob with some delay after Carol sent it! Very strange, no? This is the infamous "clock synchronization" problem. Bob and Carol agree their clocks are synchonized, but you and Alice agree they're wrong, and Bob's clock is behind (though running at the same speed as Carol's). Naturally, Bob and Carol think that Alice's clock is behind, and wonder why you blame them for the delay in sending the massage, when clearly the delay was in the transmission from you to Alice!
You could add a third group moving the opposite direction, but it would only make the brain hurt.
Consider this excellent example (the "pole in the barn" paradox). We have a spaceship flying through a galactic tollbooth. Each is 1000m long at rest. The tollbooth has two gates, closes the rear gate as the spaceship moves through, but only opens the front gate when the spaceship has paid (there's plenty of room, the spaceship is length-compressed from relativistic travel). Let's put an EZ-Tag and a reader in the middle (as best we can with
Your causality paradox for wormholes isn't *nearly* as weird as the causality paradoxes in relativity, and yet it all works.
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If a flashlight is placed in the middle between them, then from my and Alice's point the flash will reach Bob before it will reach Carol, since Bob is moving towards it and Carol away from it.
From their perspective it will reach them at the same time, so to me Carol's clock must be behind Bob's.
This way an instant message from Carol to Bob will appear to me as going backwards in time, and if it is the same message I just send instantly to Alice, then it will reach me before I sent it.
My brain is hurting already anyway
well, I am not sure if this is correct, but this is how I meant it: The clock discrepancy that is required for this paradox will be greater, the further away Alice and me are. If we are in different galaxies (but still at rest to each otherThis way I was hoping to avoid any other odd relativistic effects I might have forgotten that do not increase with distance.
Althought I have to admit that this involves some handwaving, and I probably should have just left it out.
...then from the ship's point of view it can avoid paying the toll, since the front gate has opened early and the ez-tag has not yet been read.The toll both example is very interesting, and I think this is essentially the same paradox.
But it seems that while it looks like a paradox, there won't be any actual contradiction as long as no faster-than-light signal is involved.
If the ship's front can send an instant signal to the ship's middle "Hey, I am just passing the front gate, it is already open, hide the ez-tag!" at this moment (nice illustration btw)...
But from the tollbooths frame of reference the ship's front just sent a message back in time to the ship's middle, because... Now we have a problem, did the spaceship pay or not?
As long as no faster-than-light signal is involved, the sequence migth look like a paradox, but none of the participants can do something as contradictory as in the above example.
Please tell me if that made any sense. I find this subject very interesting, althought I admid I'm in way over my head.
It's the same paradox indeed, at least if the tollbooth also has an ansible. I find this example cleaner, perhaps since it's more intuitive than "multiple Bobs".
Without an ansible there is no (additional) paradox, because it will always take a signal longer to move from the front of the ship to the middle than it takes for the EZ-tag to pass the reader. Note that this means the tollbooth always opens the front gate (whether or not the toll is paid) because there's not enough time for the reader to signal the gate.
With the ansibles, in a simple analysis, the tollbooth's signal from the reader to the front gate appears to move backwards in time from the tag's point of view, and an ansible near the front of the ship could relay that signal back to the tag alowing the tag to signal its own past. Similarly, from the tollbooth's point of view, the front of the ship is signaling the tag backwards in time.
However, I don't think that's the correct analysis. I think the signal is seen as instant from all reference frames (and the ship and the tollboth would disagree on when the signal was received, instead of its latency). Consider that the ansible works by makeing two distant points effectively adjacent. Those points are adjacent from anyone's point of view.
In the ship's frame of reference, clock 'A' walked slowly from the reader to the front gate would run faster than a stationary clock at either point, because it's picking up the time skew, and would arrive at the front gate in sync with the front gate's clock. Again in the ship's frame of reference, clock 'B' moved through the wormhole instead would (in my analysis) not pick up this time skew, and would arrive at the front gate still in sync with the reader. From the ship's point of view, clocks 'A' and 'B' would be out of sync, even though their now adjacent. From the tollbooth's point of view, of course, all these clocks are in sync.
From the ship's frame of reference, a message sent through the wormhole would be consistant with clock 'B' which made the journey on the same route, and would therefore move back in time. Both clock 'B' and the message made a 'timelike' journey, remember, not just a fast spacelike journey, and you have to account for that when thinking about the clock synchronization issues.
At least that's my analysis - I await experimental validation.
Socialism: a lie told by totalitarians and believed by fools.
Good example, but that seems impossible to me.
Here, two clocks that are next to each other and identical in structure show identical behaviour when seen from one frame of reference (tollbooth), and different behaviour when seen from another (ship).
This would imply that these clocks have a property that is different between A and B and unobservable from the tollbooths point of view.
So if we swap A and B, the tollbooth would be unable to tell which is which, but the ship could.
For clocks made of ordinary matter, such a property does not seem possible.
The ansible connects two points of space-time.
But I would say that a signal passing throught the ansible from X to Y would not neccessary be perceived as instantly from my frame. just as the signal appears to bridge a gap in space, it can also appear to bridge a gap in time, appearing at Y before or after it left X, depending on my frame of reference.
Too bad that probably neither interpretation will be confirmed or denied by experimental data in our lifetime
You never know, we haven't had a great leap forward in decades.
:)
Like the twin paradox, I don't think there's actually a problem in the two clocks being out of sync because they aren't symmetrical - they're in the same place, but they took different routes.
The twin paradox proves it's enough to take different routes to get different times. In that case, it's the acceelration of the clock that goes on a journey that breaks symmetry. In this case, it's the effectively FTL travel. Well, maybe we might find out one day, if we get another Einstein.
Socialism: a lie told by totalitarians and believed by fools.