Warp Drives Probably Impossible After All
Written by Ian O'Neill
No warp speed ahead
Just when I was getting excited about the possibility of travelling to distant worlds, scientists have uncovered a deep flaw with faster-than-light-speed travel. There appears to be a quantum limit on how fast an object can travel through space-time, regardless of whether we are able to create a bubble in space-time or not…
First off, we have no clue about how to generate enough energy to create a "bubble" in space-time. This idea was first put on a scientific grounding Michael Alcubierre from the University of Mexico in 1994, but before that was only popularized by science fiction universes such as Star Trek. However, to create this bubble we need some form of exotic matter fuel some hypothetical energy generator to output 1045 Joules (according to calculations by Richard K. Obousy and Gerald Cleaver in the paper "Putting the Warp into Warp Drive"). Physicists are not afraid of big numbers, and we are not afraid of words like "hypothetical" and "exotic", but to put this energy in perspective, we would need to turn all of Jupiter's mass into energy to even hope to distort space-time around an object.
This is a lot of energy.
If a sufficiently advanced human race could generate this much energy, I would argue that we would be masters of our Universe anyway, who would need warp drive when we could just as well create wormholes, star gates or access parallel universes. Yes, warp drive is science fiction, but it's interesting to investigate this possibility and open up physical scenarios where warp drive might work. Let's face it, anything less than light-speed travel is a real downer for our potential to travel to other star systems, so we need to keep our options open, not matter how futuristic.
The space-time bubble. Unfortunately, quantum physics may have the final word (Richard K Obousy & Gerald Cleaver, 2008)
Not so fast.
According to new research on the subject, quantum physics has something to say about our dreams of zipping through space-time faster than c. What's more, Hawking radiation would most likely cook anything inside this theoretical space-time bubble anyway. The Universe does not want us to travel faster than the speed of light.
"On one side, an observer located at the center of a superluminal warp-drive bubble would generically experience a thermal flux of Hawking particles," says Stefano Finazzi and co-authors from the International School for Advanced Studies in Trieste, Italy. "On the other side, such Hawking flux will be generically extremely high if the exotic matter supporting the warp drive has its origin in a quantum field satisfying some form of Quantum Inequalities."
In short, Hawking radiation (usually associated with the radiation of energy and therefore loss of mass of evaporating black holes) will be generated, irradiating the occupants of the bubble to unimaginably high temperatures. The Hawking radiation will be generated as horizons will form at the front and rear of the bubble. Remember those big numbers physicists aren't afraid of? Hawking radiation is predicted to roast anything inside the bubble to a possible 1030K (the maximum possible temperature, the Planck temperature, is 1032K).
Even if we could overcome this obstacle, Hawking radiation appears to be symptomatic of an even bigger problem; the space-time bubble would be unstable, on a quantum level.
"Most of all, we find that the RSET [renormalized stress-energy tensor] will exponentially grow in time close to, and on, the front wall of the superluminal bubble. Consequently, one is led to conclude that the warp-drive geometries are unstable against semiclassical back-reaction," Finazzi adds.
However, if you wanted to create a space-time bubble for subluminal (less-than light speed) travel, no horizons form, and therefore no Hawking radiation is generated. In this case, you might not be beating the speed of light, but you do have a fast, and stable way of getting around the Universe. Unfortunately we still need "exotic" matter to create the space-time bubble in the first place…
Sources: "Semiclassical instability of dynamical warp drives," Stefano Finazzi, Stefano Liberati, Carlos Barceló, 2009, arXiv:0904.0141v1 [gr-qc], "Investigation into Compactified Dimensions: Casimir Energies and Phenomenological Aspects," Richard K. Obousy, 2009, arXiv:0901.3640v1 [gr-qc]
Filed under: Physics
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April 3rd, 2009 at 3:15 pm
Bummer. Wormholes it is then.
Is that a Cardassian ship in the figure?
April 3rd, 2009 at 3:45 pm
Hi Ian.
I disagree with you from your first paragraph since this is my view here… Forgetting about the power needed etc…, some of that is likely true, it's your opening statement where I think you've gone astray here and so the opening premise is in question.
Inside the warp bubble, you create your own pocket of space-time which runs at the same time speed as what we consider "normal" space-time which is what we experience every day – this is why no-one ages any different when travelling at warp speed from those whom are not. So, you, yourself, and your ship are not travelling faster than light so that cover's the Einstein Laws bit. So what's left leads to thinking that the bubble is moving faster than light as you imply here – but is it really?
Actually, it's more-easily thought of as the fact that you are creating your own new space-time inside of space-time with an interface between the two (the warp bubble). This interface is outside of either space-time regions and thus cannot be governed by space-time laws since the interface is what warps space-time. So, you might think the warp bubble is moving faster than light through "normal" space-time, but in fact it's not, it's the interface between the two if anything at all since you are warping the "normal" space-time with your warp bubble. However, since the interface is outside of either space-time, no-one is actually travelling faster than light and thus do not break the quantum limit you mention in your opening paragraph!?!?
The rest, well, power needed, etc…; perhaps they are unlikely, but as for the quantum limit, this is not the cause of any inability to put together "warp drive".
Feel free to rebuke my remarks, it's not often I disagree with your articles…
Take care,
Mario.
April 3rd, 2009 at 5:03 pm
Saying 10 to the 30th is not far off of 10 to the 32nd is the same as saying 10 is not far off 1000
April 3rd, 2009 at 5:36 pm
That sounds like the same kind of stuff that was said about faster than sound travel.
just kidding
April 3rd, 2009 at 5:43 pm
If the theoretically impossible was theoretically possible, then the theory regarding that theory would make it impossible… in theory.
Personally I think its much ado about nothing.
We don't know enough on how to make any such thing happen in the first place, so saying it cant be done is just as far fetched a notion.
If you want to enable realistic space travel within the (relatively) near future, work towards extending the human life span or find some kind of suspended animation system that works.
Its possible to get ships up to a high enough speed that they could span the distance between stars in less than a century.
What we need is to find a way for the crew to survive that long.
In theory we could populate most of the galaxy in just a few million years using current day technology.
April 3rd, 2009 at 6:28 pm
Max, there is no real problem with working both fields. The odds are that sub-light interstellar travel will be the first and possibly the only practical solution, but there is certainly no reason for the theoretical physicists to give up on the search for a superluminal solution.
Until there is some real breakthrough, it's all theoretical anyway, so it's not like they're spending a lot of money chasing possibilities.
April 3rd, 2009 at 6:39 pm
These types of solutions involves violations of the weak energy condition (WEC), or that the momentum-energy tensor is such that T^{00} < 0. The problem is that the quantum fields which make this source of spacetime curvature are quantum mechanical. due to the violation of the WEC this means that the eigenstates of the field which acts as this spacetime curvature source is not bounded below. This means that a particle of this field can cascade down an endless ladder of energy states and emit an infinite amount of energy.
This means that the negative energy field becomes swamped by more positive energy, which is what Ford and Roman call the quantum interest problem. This destroys the spacetime configuration. Hence these types of solutions are not stable. The wormhole shares this feature along with the warp drive.
Lawrence B. Crowell
April 3rd, 2009 at 6:48 pm
I should mention two other things. A tachyon is really a sort of micro-warp drive. These exist in the 26 dimensional bosonic string sector, but vanish in the RR and NS sectors.
This analysis appears useful as a way of demonstrating that the big rip or phantom energy does not exist. It seems that the cosmological horizon would be unstable.
Lawrence B. Crowell
April 3rd, 2009 at 7:36 pm
I don't care what they say! I still plan on seeing the new Star Trek movie in May.
April 3rd, 2009 at 7:55 pm
We already know there is a limit on faster than light speed, it's called warp factor 10. We just now have to wait for a drunken physicist that like 60's music on a juke box to overcome these problems.
April 3rd, 2009 at 9:42 pm
"We already know there is a limit on faster than light speed, it’s called warp factor 10."
In the Star Trek Universe (except the original series) Warp 10 equals infinite velocity.
I could live with than kind of limit…
April 3rd, 2009 at 10:16 pm
Spacetime is a myth.
"In a nutshell, Pastor Al [Einstein] was deluded into thinking that space is a physical object." — Bill Gaede, physicist, 2008
"…it is not necessary to refer the law of inertia to a spacial absolute space. On the contrary, it is perceived that the masses that in the common phraseology exert forces on each other as well as those that exert none, stand with respect to acceleration in quite similar relations. We may, indeed, regard all masses as related to each other. That accelerations play a prominent part in the relations of the masses, must be accepted as a fact of experience; which does not, however, exclude attempts to elucidate this fact by a comparison of it with other facts, involving the discovery of new points of view." — Ernst Mach, physicist, 1893
"If we…consequently take objects as they are in themselves, then time is nothing." — Immanuel Kant, physical scientist/philosopher, 1781
"Time is not an empirical conception. For neither coexistance nor succession would be perceived by us, if the representation of time did not exist as a foundation a priori. Without this presupposition we could not represent to ourselves that things exist together at one and the same time, or at different times, that is, contemporaneously, or in succession." — Immanuel Kant, physical scientist/philosopher, 1781
"When formerly I regarded space as an immovable real place, possessing extension alone, I had been able to define absolute motion as change of this real space. But gradually I began to doubt whether there is in nature such an entity as is called space; whence it followed that a doubt might arise about absolute motion." — Gottfried W. Leibniz, polymath, 1695
"…space without matter is something imaginary…." — Gottfried W. Leibniz, polymath, 1689
"There is no vacuum." — Gottfried W. Leibniz, polymath, 1689
"…we must raise the whole problem about place/space — not only as to what it is, but even whether there is such a thing." — Aristotle, Physics, Book IV
"…if it [place] is itself an existent, where will it be? Zeno's difficulty demands an explanation: for if everything that exists has a place, place too will have a place, and so on ad infinitum." — Aristotle, Physics, Book IV
"It is evident, then, that it is easy to refute the arguments by which they prove the existence of the void." — Aristotle, Physics, Book IV
"…there is no void…." — Aristotle, Physics, Book IV
April 4th, 2009 at 1:17 am
"In the Star Trek Universe (except the original series) Warp 10 equals infinite velocity.
I could live with than kind of limit…"
The real limit is that you will evolve to a lizard in 24hrs and have little lizard babies with Captain Janeway.
April 4th, 2009 at 2:14 am
hmmm – Bill Gaede has joined the ranks of people cited by some of those who comment, indicating that people seem to exist who believe that he's "for real".
I'm gradually beginning to believe the "2012 End Of The World" event is for real, but not by comet or Planet X – rather more likely due to an accretion of gobbledygook on the communications channels.
Feenixx feels distracted and disturbed and must go out for some retail therapy to cheer himself up……..
April 4th, 2009 at 4:02 am
Oh, Mr. Kant, what a good idea! Lets just tell the laws of physics that they don't exist, and then they won't. We can do whatever we want then. After all, the Universe was built for us to play with, so of course anything is possible.
I think that mining phantom Jupiters to build spacetime bubbles is a great idea. Never mind all those life-supporting exomoons that orbit them… they're just ants on an anthill, full of silly microbes anyway.
Cosmic preservationism, indeed.
April 4th, 2009 at 5:10 am
MK: As an aside I have certain sentiments along those lines. I am opposed to the idea of sending astronauts to Mars in part because they would doubtless leave a mound of garbage behind and contaminate the place. This would be noise that would obscure the search for martial life or signatures of pre-biotic chemistry. A lot of these ideas of us colonizing space are pretty ditzy IMO. The idea of humans pushing into the universe to colonize all that is possible to conquer strikes me as similar to a flea climibing an elephant's butt with rape on its mind.
The Alcubierre warp drive solution is interesting as a research model. The warp drive involves shoving points of space together in one region by tightening up Calabi Yau or K3 spatial scales and correspondingly enlarge these scales elsewhere to move points apart. I has been known that this results in horizons which prevent one from being able to causally connect this spacetime region together. Now it turns out it leads to runaway Hawking-like radiation that renders it unstable. Might it be that this is telling us something about the scaling of gauge physics and fermionic masses in the universe?
There is the whole issue of fine tuning of these parameters, which might be called something else: critical renormalization flow (CRF). At the Anit de Sitter (AdS) spacetime boundary a conformal field theory (CFT) at high energy exhibits a simple renormalization group (RG) flow according to the geodesic arcs on the hyperbolic AdS, similar to the arc on the Poincare disk. The low energy theory, where the curve returns to the boundary, appears the same as the high-energy theory. This is because there is no intrinsic scale — the AdS is conformally invariant. But if you perturb the theory by adding mass terms to certain fields, the RG flow is nontrivial and one obtains a different theory at low energies. The conformal fields or CFT are equivalent to the AdS, by Maldacena et al, and at very low energy addition boundary conditions enter into the physics. This is I think tied into the conformal infinity of AdS as a timelike space, which requires additional BC information on top of spatial surfaces for their specification. So this appears to be the endpoint of RG flow by AdS arguments.
Might it be that the mathematical problems of the warp drive are telling us something about the RG and why the universe "selects" a critical RG? We might not get to alpha centuri at war speed, but we might learn something about the structure of the universe.
Lawrence B. Crowell
April 4th, 2009 at 6:00 am
Dr. Crowell,
I'm interested in reading more…do you recommend a text that you or someone has written?
April 4th, 2009 at 6:14 am
If you are spun up on this sort of physics I would look at Juan Maldacena's seminal paper
http://arxiv.org/PS_cache/hep-th/pdf/9711/9711200v3.pdf
If not then you can look at Susskind's book "Black Hole Wars," which gives a description of the AdS/CFT duality.
Lawrence B. Crowell
April 4th, 2009 at 7:16 am
You guys do realize that the Alcubierre warp drive model was superceded by something from Baylor University that doesn't break the laws of physics, right?
April 4th, 2009 at 7:47 am
I read this elsewhere recently as far as memory serves.
Disappointing but interesting stuff as it is good to see people discussing the possibility of faster than light travel.
We still have our dreams.
April 4th, 2009 at 7:57 am
So, radiation would cook our fragile biological bodies?. If we do at some point in the future become a spacefaring species, I doubt we will still be biological entities.
Always did wonder about the human desire to create robots in our likeness.
And if we are no longer bound to our short lifespan, there is little reason to travel faster then light.
Damian
April 4th, 2009 at 8:27 am
I think this research is actually a step _forward_ in FTL travel/the physics of FTL travel.
April 4th, 2009 at 10:16 am
Wait…where is the p=C2 ? I don't see it. No wonder that his warp bubble is unstable.
April 4th, 2009 at 10:24 am
I know, I know;
And I am old enough to remember when physicists conclusively proved that:
1. Bumblebees could not fly.
2. A rocket ship big enough to put a man in space was not possible.
3. An aircraft could not survive breaking the sound barrier.
4. ect, ect, ect.
Old School
April 4th, 2009 at 10:30 am
Well, there are always a few problems with new technology, it has never stopped us before and will not this time either. We shall find a way of travelling faster than light sometime or other. We are a clever race, the only clever race in the universe. Roger.
April 4th, 2009 at 12:06 pm
Patrick, many of those assumptions were made by people not taking advancements in technology into account.
If you asked someone in the 1800's how a man can fly they would have either suggested a hot air balloon or something involving birds tied to a chair.
If you then asked them if it was possible to break the sound barrier or go into space they would obviously say no.. after all, there aren't enough geese in England to make that happen.
Its a correct assumption because they didn't take into account the advancements we would make in duck breeding.
April 4th, 2009 at 1:00 pm
Once we stop wasting time trying to figure out how to move matter the speed of light, and focus on moving energy, energy with the necessary information to transform back into matter at the end of its journey, we will have solved the travel at the speed of light problem. The universal fax machine…
April 4th, 2009 at 1:03 pm
Agreed. Clearly, if humans obtain the ability to control 10^45 Joules of energy, their technology will be able to control the ensuing runaway Hawking radiation. They will most probably recycle this immense radiation back into the warp field. I'm no physicist, but my engineering gut says so. If only I could build it!!
April 4th, 2009 at 2:23 pm
"You guys do realize that the Alcubierre warp drive model was superceded by something from Baylor University that doesn’t break the laws of physics, right?"
http://dsc.discovery.com/news/2008/07/28/warp-speed-engine.html
its the same exact thing as what this article is saying cant happen. Go research next time
April 4th, 2009 at 4:32 pm
@ stephan, Sorry to disappoint you, but Discovery.com postings do not really amount to much compared to peer reviewed papers in scientific journals. Does make for nice daydreams, though. You really need to "Go research next time ".
April 4th, 2009 at 4:45 pm
@Stephen- I read the Discovery Article- Lots of science fiction in that one- First you have to travel to the twilight zone – aka the 11th dimension- who knows if that one really exists-Then according to the article you would have to covert the entire mass of Jupiter into energy-10^45 joules- this in itself is a tricky process.
I try to be a practical type person when it comes to Science- Since we do not observe anything except for light itself, traveling as fast as light- then it is unlikely that the laws of the universe will ever allow us to travel faster.
You know those guys who wrote the article are correct- we would have to leave our known universe to make such an attempt.
With all of that said- I really hope that I am wrong. It’s a shame, wouldn’t it be neat to go tearing across the universe in a starship.
April 4th, 2009 at 6:06 pm
None of these articles ever take into account the fact that it's possible to travel without traveling…
On the quantum level, it is entirely possible for information to be transmitted from point A to point B *instantaneously* – effects known under names such as quantum teleportation and quantum tunneling. So what would happen if we came upon a technology that allows quantum scale physics to effectively scale up to the macroscopic?
April 4th, 2009 at 6:46 pm
About ftl travel, people have to start thinking outside the box, or in this case, outside the relative level of the universe. There is an infinite transcendental level and it underlies the relative. To go from any place in the relataive, all one has to do is go to the transcendental field and travel through it to anywhere in the universe one wants. How does one do that? Do search for "yogic flying." That's the start.
April 4th, 2009 at 9:44 pm
Never say NEVER. I have been looking at my proof of Riemann hypothesis and I have prescribed on several occassions on other websites: Nothing is impossible. I have been intermingling the steady states of the Mev of electrons amongst the values of the black hole senario that Dr. Hawking has advised. The awesome one phenomenae is the proof reveals a dominance of the number six. Yes a little known number : 6. I have considered many reasons why the number six has confirmed it]self but until recently, i have not been unable to discover this 'dominance'. The spatial are starting to breach upon a dependence on a further 3 spatial. it is hard to say if they are a repulsive 3 spatial or an additional 3 D spatial that may propagate an appearance of a repulsive state. I consider this an accerated divergant state that can 'mimic' a repulsive state, but remain a convergent state. A simple 3D state may seem more than the eyes can see or are willing to accept.
As those have observed the rotation of the complex function of the RH, most are perplexed as to why the near zero circumferences, The centripetal force is starting to reveal a system of the dominnance of the number 6 and a 'repulsive force' is possible now that an outside complex function is causing the zero-narrowing function that 'appears' to be an attractive force is actually a repulsive force acting in concert causing the state of the ever succession of zeroes. Fifteen years of work requires a few more years but I have to say that the number six is now finding a significance.
The einstein Special Relativity is an intricate network, but many have tried to understand why galaxies do not fly apart and/or what is dark. I have proposed on occassion that the web of the universe is comprised of a repulsive force in between all galaxies and we are not just a symptom of like attractions . Robert Forward has done some work on the subject, but I will finish it.
Don't be so sure that the time travel or anything else will be impossible. Outside our galaxy, we are all waiting for answers. I have an answer as to why our galaxies do not fly apart and the web of the universe as seen by Einstein is close, but needs more info.
The number 6 people is very important.
And yes! I have the proof of RH and have been hanging on to it for 2 years now. I'm just one of those guys that love math and have been working behind the scenes without an influence that this is wrong. Don't go here. Don';t do that. Don't do this. I am my own man doing my own thing. And the answers are coming. But more answers are still to come.
Have a nice day and remember just because the physics of what we know now is telling us that something is not possible, the picture may not be fully revealed yet.
April 4th, 2009 at 10:02 pm
say that again?
April 5th, 2009 at 3:56 am
As for exotic fuel needed for this venture why can't someone use nuclear waste that sits under Nevada and other places to develop this? I am sure there will be some uses for these wastes. Just a thought
April 5th, 2009 at 5:06 am
Todd said
"Never say NEVER. I have been looking at my proof of Riemann hypothesis and I …."
Thats when I stopped reading and went to have a cup of tea.
April 5th, 2009 at 5:17 am
The Discovery article concerning the Baylor researchers appears to reference a similar idea. A little general relativity might be in order. The field equation says that spacetime curvature information is equal to the matter or energy source of that curvature. That source is given by a tensor, similar to a matrix, which for cosmology is given by
T^{ab} = K(e g^{ab} + pU^aU^b)
for K = 8pi G/c^4. Now this might be broken up a bit. The time-time component of the matrix is just e, the mass-energy so T^00} = Ke. The spatial parts are T^{ij} = KpU^iU^. With inflationary cosmology the pressure term p is negative and p = -e. For this reason the spatial surface of the early cosmology was stretched out. Particles were then carried along, and the relative velocities between particles could indeed be faster than light! However, no actual violation of relativistic rule, "thou shalt not violate the speed of light." The reason is that this is a rule for a local flat region, but a spacetime with curvature can have different local regions where the light directions (light cones) differ. So this "Baylor scheme" is an idea which exploits the same idea.
I attempted over 10 years ago to work on precisely just this, and I ran into troubles, The negative pressure might be thought of as a strange sort of spring. If you extend a spring it exerts a force opposite to the direction you pull it. With negative pressure the analogue would be a spring that once extended exterts a force with the force you exert. So let's suppose you can create a bubble where the symmetry of the vacuum is the same as the Lagrangian and you recover inflationary pressures. If we had a sufficiently powerful accelerator we could do this in fact in a small region defined by a nucleon. Then what does this negative pressure act upon? It will act upon the bubble itself and inflate it away faster than one could generate enough energy to keep it stable. This was a problem that I ran into with this.
Now consider this as a "rotation" of the Alcubierre warp drive from one with a negative energy T^{00} < 0 to one with a negative pressure p < 0. This amounts to a transformation of a timelike quantity to a spacelike quantity. This is not premissible in relativity theory. In effect one is attempting to cross the light barrier if the Alcubierre warp drive can be transformed into this form which does not violate the weak energy condition. The null geodesics, curves that light rays follow, in the two spacetimes remain invariant. The invariance of null conditions is a cornerstone of relativity. Then as a result it appears that it is not possible to have a warp drive with p < 0 which is stable while one with e < 0 is not.
Lawrence B. Crowell
April 5th, 2009 at 6:47 am
"UKDave Says:
April 5th, 2009 at 5:06 am
Todd said
“Never say NEVER. I have been looking at my proof of Riemann hypothesis and I ….”
Thats when I stopped reading and went to have a cup of tea."
I understand your resistance to accept. If such a claim is not a true proof, I have come to the conclusion that I am okay with that. I discovered this math tool in 1998 and plugged it into RH and with a lot of elbow grease, I finally saw the path. It jumped out at me. You are not the first to resist my claim. I don't mind. I expect it.
I am stronger at the math than the physics and there is definitely a possibility for errors in the physics realm.
My whole body of work is in notepads here and computer progs there, but it seems to be all pointing one way.
I have an axiom that uses asymptotic levels of 1 for all numbers. This is my attempt to solve Cantor's Continuum. This axiom reveals a state that has the accelerated divergence that mimics a convergence. I have usually treated these as independent, but until recently I started looking at them as a concurrent state. A light bulb went off, but now I have to ind the room that is light up. I just keep plugging away. I try. If you don't try, you don't know.
You can scoff at me. That's okay. I will be many years yet to finish the grand piece. I am not going to share my work until that time… maybe. So, mostly I try to refrain from putting myself out there.
BUT I DO BELIEVE "NEVER SAY NEVER"
My brain is open and will always be that way.
Todd
April 5th, 2009 at 7:21 am
The EMF is 10^42 times greater than gravity
So if we produce an EMF bubble to protect us as we attempt to travel in space time we will isolate ourselves from this space time & will not be able to navigate
It seems that star travel for us is a one way trip either because of our short life spans & the vast distances or time dilation at super luminal velocities
If & when we returned everybody we knew would be long dead
Passing through event horizons is not a survivable option
April 5th, 2009 at 7:23 am
Scientists are always telling us how many things are impossible.
Then someone ignores them, figures out a way to do it, and we move to the next level.
April 5th, 2009 at 7:34 am
A comment earlier that if something is possible then it should be observed in nature is on the mark. Powered flight clearly existed before the airplane, they were called birds. Rocket flight was really just an extension of Newton's laws and planetary motion. Achieving these, such as getting a power source which could loft an airframe or controlling rocket thrust were difficult, but not fundamentally impossible.
With the warp drive the physics is related to issues of time travel. Time travel is if nothing else a near logical contradition. There are complicated arguments around this, such as the grandfather problem (going back in time to kill your parents or grandfather), but these arguments tend to be specialized or "brittle."
There are clearly obstructions to warp drives and wormholes and other things. Check out the Krasnikov tube while you are at it. These obstructions may not be absolute impossibilities, but they so far suggest something fundamental about the world which requires proper causal ordering so that global and local principals have a logical correspondence. Clearly physics and cosmology probably is not the Charlie Parker "anything goes," which does mean there are constraints and obstructions, which likely involve these strange spacetimes.
The warp drive and wormhole are of course still interesting as theoretical tools. One might ponder whether there are quantum warp drive configuations — that is worth considering! These are probably related to tachyons, and these play a role in constraints on string theory. It is though very unlikely we will ever see them manifested at large or as technologies.
Lawrence B. Crowell
April 5th, 2009 at 9:26 am
"A comment earlier that if something is possible then it should be observed in nature is on the mark." -Huh?
The following things are therefore impossible:
1) Life going to the moon.
2) Plastic
3) The Internet.
4) Steel
5) Gasoline
Can't get anymore wrong that that!
April 5th, 2009 at 10:45 am
And what if the human was to evolve to pure energy, say like (Q)
And even this fictional character had a very dim view of humanity.
The dinosaurs existed on earth for over 200 million years, in comparison the humans have the means and the mind to end their own existence in a cosmic blink of an eye
April 5th, 2009 at 11:57 am
Life going to the moon: It probably happened long before the Apollo program. Asteroid impacts probably sent bacteria baring rocks to the moon, maybe to Mars as well
Plastics: Tough to call, but it is not impossible that they might exist on other planets with the right chemistry.
The internet: In a sense bacteria on Earth form a sort of global biological internet.
Steel: A form of alloy, and alloys of iron and nickle exist in meteroids. Not exactly steel, but close enough.
Gasoline: It is just a component of petroleum, or fossilized algae, which we separate out in columns that we call refineries.
Lawrence B. Crowell
April 5th, 2009 at 12:55 pm
Lawrence Crowell- You left out the fact that none of jojo's items have ever been observed traveling anywhere near the speed of light!
Please keep your comments coming- I enjoy them all- You are a learned man and we need you here on this site to help us understand these matters in your objective manner.
April 5th, 2009 at 1:06 pm
Correction- Well maybe the internet travels the speed of light- but still not at warp speed.
April 5th, 2009 at 2:19 pm
I think a question worth exploring is proper time and what is the proper time everywhere. All the elements exist for there to be a chocolate truffle cake randomly floating through space. Seemingly not plausible but the elements of existence order themselves to a point. Intelligence takes those elements and configures them in a certain way to achieve a chemical mix beyond this primal level. It's like the Darwin version of elemental evolution. The elements exist. We configure. Then we manipulate that configuration.
Proper time is a not something we can ascertain with our existence on one planet. We send out probes. Like now we see an extreme solar minima. What happens five minutes from now that was proper time at the Sun and is now five minutes in the future?
So warp drive will require knowing the proper time of your journey. Go on a trek in the woods. Look at a map. You know where you are going to go, but you discover a chocolate truffle cake in the path. Do you eat it, examine it, or discover how it got there. What if part of the path is washed out? You have to adapt. I'm rambling but my point is, if you are travelling at light speed, anything can cause the journey to come to a screaming halt.
Now also you need to know the proper time of the destination if you can warp space. It's no good to go to a place that has an exploding star on the rise.
We can only surmise to take precautions on extrapolated data — what seems safe.
These are obstacles but not impossibilities.
The whole idea of spacetime being warped is good to know and things like the WMAP, but what is the proper time of everywhere?
That is… look for a spacetime 'warp' that isn't there. Observe this? Yes with the proper mathematical tools. The ones that account for dark matter, dark energy, etc. and some sort of EM manipulation.
The tools and formulae now used are based on what we have deduced to be true. What if another ingredient put into this physics and mathematical cog changes the existing formulae to allow time travel which doesn't 'cook' us or cause a collapse in a worm bubble? We need a 'proper' space'time' bubble.
Whatever the outcome, we have to expect something is missing in our platform of understanding. I am not trying to change the world, just trying to open some minds.
Todd
April 5th, 2009 at 3:25 pm
The proper time of the spaceship being carried along with the warp bubble is easy to compute, trival in fact. it is just the flat spacetime result. Now a proper time everywhere does not exist. There are horizons which causally disconnect the warp bubble. This is why the thing can't be controlled. So a cloud of test masses in the entire spacetime region will have proper times or intervals which can't be transformed into each other.
Lawrence B. Crowell
April 5th, 2009 at 3:35 pm
We know way too little about this subject to be discounting it already. And the comment that the "Universe does not want us to travel faster than the speed of light." is nothing short of anthropomorphizing nature. The universe may not care whether we travel faster than the speed of light. We don't know. Sounds like the author doesn't want us to.
April 5th, 2009 at 4:00 pm
Our knowledge will progress as the LHC at CERN begins smashing particiles together later this year.
The key is DARK ENERGY.
However I do not believe that the Human Race will live long enough to develope major space travel.
We are Hardwired to Destory ourselves.
Nature may beat us to the punch.
The history of the Earth shows that the planet appears to allow speices to grow and prosper.
Right when they feel that they are MASTERS of the Universe Nature steps in and puts them in their place, which is called EXTINCTION.
Sir Blasphemy
WORLD CEMETERY 2012
April 5th, 2009 at 7:00 pm
I've never believed in the possibility of material faster than light travel (or time travel) in itself. However, I believe we could possibly perceive and communicate, or even achieve virtual "presence", at vast distances through quantum transmission. The key word is virtual. This could be done by perceiving the vibrations or emanations of matter on the space fabric of one place and and transmitting this through the universal energetic continuum of pure space (or the "ether", which unfathomable fabric will probably always remain the ground of perceivable physics and communications). Television and radio work this way, by transferring virtual images and sounds as pure energy waves which are reconstituted illusions on the other end, but nonetheless transmit a great deal of info about the original place. Would this require a quantum "transmitter" at the other end? Maybe or maybe not…Likewise as our knowledge of matter gets deeper, we may be able pick up emanations of matter from past or future times, by perceiving how the space-time fabric has been changed and effected, by means of quantum "antennae" tuned to a theoretically pure state.
Meanwhile, I've noticed no mention in UT of the "photon prescience" experiments of this past year (where photons exited an experimental chamber before they entered it) or the Templeton Prize winner (who claims and demonstrates how quantum observations reveal a greater "veiled" reality not consistent with material physics). We will only get to the future by accepting all the data as it honestly appears to us, rather than pre-selecting data to fit a strictly materialist, or pre-quantum world view.
April 5th, 2009 at 7:57 pm
While quantum mechanics exhibits nonlocal effects and entanglements, it is not possible to communicate actual information faster than light this way. The barrier on travelling faster than light is really a limit on the speed with which information can be communicated.
Lawrence B. Crowell
April 5th, 2009 at 8:06 pm
"THE OFFICIAL DOOMSDAY COUNTDOWN WEBSITE"
Lovely. Another loony.
The whole website appears to be a front to sell merchandise.
April 5th, 2009 at 9:49 pm
It seems I started quite come debate here…
April 5th, 2009 at 11:51 pm
I think as our technology develops we might be surprised to find faster then speed of light is not only possible but more common then we think. Also the whole time being a human perspective we might find it would be better to travel through another dimension in some sort of loop. This may open the possibility of time being a destination. Like going to the shop but there is more then one in the same street, they are all the same shop but in different times. Just some out of the box ideas not meant for any serious discussion.
April 6th, 2009 at 4:52 am
I suspect that navigation at superluminal velocities will prove to be the biggest obstacle of all.
April 6th, 2009 at 6:41 am
Faster then light travel! Warp drives! Wormholes! Tachyons! Quantum physics! Gawd, I hope all this scientific speculation is not based largely on Wall Street mathematics!
April 6th, 2009 at 10:43 am
Why do we speculate, or bother questing, when we have Lawrence B. to set us straight?
SInce he has all the answers, why don't we just hand the universe to him and sit back and sip our sodas?
April 6th, 2009 at 11:33 am
If space expands enough, then light can be redshifted down to microwaves, and eventually to the point that it is not observable.
What about an object traveling FTL. Would any EM rediation be emitted or reflected from it?
April 6th, 2009 at 12:51 pm
come on even space goes faster than the speed of light-don't give me this bullsh*t. and if this is true we should be seeing this hawking sh*t happen everywhere because there are gravitanol waves going through all of space and that space is moving faster than light(the inflation and also dark energy effect ) .he must have forgot that one.go over it again buddy.
April 7th, 2009 at 6:05 am
"he must have forgot that one"
*You* are forgetting that the stuff you are mentioning doesn't have any mass. Photons move at the speed of light because they have no mass. If something has mass, the mass increases with speed, thus requiring more energy to go faster, and then you attain more mass, and need more energy, and so on.
And how does "space" travel faster than light when space is nothing? Nothing has speed?
April 7th, 2009 at 4:14 pm
Believe me, I don't know it all by any stretch! I do know a thing or two about general relativity. I also think on a broader basis that nature can only exist if it is self-organized according to principles which don't lead to contradictions, or 0 = 1. The problem with warp drives and related spacetimes is that if they are possible then time travel is also possible. This leads to causality paradoxes, such as the old conundrum of going back in time and killing your parents before you are conceived.
Lawrence B. Crowell
April 7th, 2009 at 4:17 pm
I think a good place to start is right here at home with time travel. One big obstacle is defining the space that must be used and I say that we don't have to go right to light speed to do this. Our galaxy does speed through space. The first problem is to define the time without disturbing the space…. like a timeless bubble that can remain in a given space. It would be very hard initially to define a future space that the galaxy will travel to, in order for your body (or whatever object) to 'catch up' with the given space. In the former idea, future travel will be possible — a one-way mission. HG WELLs right?
The second small step.
Todd
April 8th, 2009 at 12:29 pm
The Universe does not care what I think.
(Referencing pathetic fallacy)
So, you know, said Universe probably won't stop me from FTL or time travel.
This form of (warp drive(1)) might well be impossible, time travel might be beyond impossible(2) but I do think that FTL will be possible some day.
Personally, I would re investigate the speed of gravity paying particular attention to the idea that since gravity waves do not have an EM component then they should not be constrained by the speed limits applied to photons(3).
I would then take a closer look at dark matter and Brane/M theory.
(1)warp drive and wormhole are two phrases that annoy me; but no one else seems to care.
(2)Really, there is more evidence for UFOs and Psychic fruitloop foolishness than the possibility of time travel; what is wrong with people?
(3) Maxwell's equations, damnit. Whenever anyone mentions universal policeman in my presence I am tempted to hit them; see first paragraph.
April 12th, 2009 at 1:45 am
Great stuff. Nice to read some well written posts that have some relevancy !
April 22nd, 2009 at 8:12 am
OilIsMastery, what point is it supposed to have to quote philosophers on physics? Especially philosophers who died before the physics we're talking about was worked out?
Do you have any idea what 1030 K means…? Hint: everything becomes a plasma at 104 K, and somewhere around 1012 K, IIRC, everything becomes a quark-gluon plasma.
They showed that bumblebees can't fly the way an airplane or most birds do.
Guess what, they were right. Bumblebees don't fly that way. They fly more like how hummingbirds hover.
How is that supposed to work? Particles interact with each other. That's the "observation" that makes the wavefunction collapse. Yes, it works with C70 molecules, but the bigger an object, the more difficult it gets.
Unless perhaps if we cool stuff down till it forms a Bose-Einstein condensate. Ha, ha.
Show us. Put up or shut up. Publish.
Then why didn't you publish long ago!?!
That's ordinary matter, not exotic matter. Exotic matter is what the LHC will maybe produce – one particle at a time…
As an evolutionary biologist, I can't fathom what you might mean.
Complete nonsense.
…which move at the speed of light.
Besides, have you got any evidence for those "vibrations or emanations of matter"?
How dare anyone know more than you.
Go study quantum physics, and then come back to explain why he's wrong. I wish you good-afternoon. See you in 10 years. <wave>
Not to photons. To massless particles (such as gravitons) in general. To information in general even.
April 22nd, 2009 at 8:15 am
So <b> and <blockquote> are allowed, but <sup> and <sub> aren't… of course "104", "1012" and "1030" are supposed to mean 10^4, 10^12 and 10^30, and "C70" is C with subscript 70…
And relativity, obviously. Could still be feasible in 10 years, though.