Talk:Spacewarp

Original version

Concerns about this article:

• The article appears to heavily use terms that are not generally standard within the physics community ("energy strings", "timewarp", "transwarp", and arguably "spacewarp" itself). The closest matches (superstring, time travel, time hole wormhole variant, and Alcubierre drive, respectively) have meanings quite different from the ones apparently intended here, while "space warp" is ambiguous enough to be meaningless.
• The article refers to "several theoreticians", but doesn't name any of them or cite their work.
• The article appears to be trying to present itself as a technical article, but the only citation present is a work of fiction.
• The article claims "spacewarp" and manipulation of "energy strings" are a feature of the "Contact" film/novel, but the actual mode of transportation used in the novel and the movie adaptation involves wormholes.

If there are bona fide physics publications using these terms, please cite them and adapt the article to explain them more clearly. Otherwise, this should probably be deleted. --Christopher Thomas 06:52, 5 Mar 2005 (UTC)

Replacement version

Right, so I'm not the original author, but this term is used by Alcubierre and those theoreticians who now work on Alcubierre's solution to GR equations. I've added some clarifying information, deleted the reference to Contact (didn't quite understand that one myself) and tried to give an overview of the concept as distinct from the Alcubierre drive itself. Still needs work, though. S.N. Hillbrand 03:43, 6 Mar 2005 (UTC)

While your version of the article is far better than the original, wouldn't most of this material be better off merged with the Alcubierre drive page, as opposed to being under "spacewarp"? It seems to be exclusively discussing the Alcubierre drive and its variants. If there are other works which propose drives with similar approaches but very different implementations, then I can see keeping it (or at least making it an index page to these implementations' main pages), but I'm not really sure there's much here that justifies its own topic, at present.

Minor nit-pick in an otherwise good article: If I recall correctly, the node ahead of the craft has positive mass, while the node behind has negative mass. --Christopher Thomas 05:52, 6 Mar 2005 (UTC)

As I was writing this, I considered the possibility of merging the articles. On one hand, the articles describe similar ideas, but I think that spacewarp has some distinct features that I will attempt to bring out in time. Specifically, the Alcubierre drive requires globally hyperbolic, non-connected geodesics. Further work suggests that this condition is not required and that warping space around 3+1 dimensional bubble would satisfy WEC with both non-hyperbolic and (in 2+1), kinked geodesics. I think this page might be a good place for greater explanation of the geometry of warping space in this manner, whereas the Alcubierre drive page could provide a layman's overview of the concept put forward by Alcubierre.

You may be right on the pos/neg energy distributions, I will re-read the papers to check this. Off-hand, though, a negative energy distribution in front of the bubble would cause a Casimir-like effect of pushing space toward the deficit, while a positive distribution would expand the space (e.g. the Big Bang).

I am extreamly not against merging the wormhole article and this article. Wormholes and Spacewarps, even if they are not the same thing, are very simliar, so similar that, I think we should merge the articles. Besides, spacewarps make me think of sci-fi, while wormholes make me think theoretical physics. Theoretical physics, rather than sci-fi, sounds like what this article is going for.

Wormholes and the Alcubierre drive use related fundamental physics, but are not the same. They are both real physics concepts, whatever they may make you think of. Maybe the article does use too much fictional reference, but warp drives did exist in fiction before the real scientific concept was developed. SpaceCaptain 18:11, 12 Apr 2005 (UTC)

Mac- Let me know what it is about spacewarp that makes you think of science fiction. In editing the page, I stuck directly to the science of the subject. I'm not certain what about this makes you think of wormholes, though. Wormholes and spacewarp are definitely distinct concepts, not the least because they are separated by the Cauchy Horizon (and therefore could not meet in spacetime). S.N. Hillbrand 02:11, 13 Apr 2005 (UTC)

Rewrite for accuracy and WP:NPOV

This article cites a highly selective portion of the extensive literature on warp drives and related concepts like quantum inequalities (relevant to the question of whether large negative energy densities can be attained or sustained). The current status of this concept is much less optimistic than the article would have you believe. It is by no means undisputed that problems have been "solved" as claimed in the article. See the arXiv.

This article appears to be trying to discuss the same topic as Alcubierre metric, but from a biased point of view. ---CH 21:48, 24 December 2005 (UTC)

Misleading claims in current version

They include:

1. "Many of the problems with the Alcubierre drive were resolved by Chris Van Den Broeck in 1999 in a paper also published in Classical and Quantum Gravity. By contracting the 3+1 dimensional surface area of the 'bubble' being transported by the drive, while at the same time expanding 3 dimensional the volume contained inside, Van Den Broeck was able to reduce the total energy needed to transport small atoms to less than 3 solar masses." Actually, this is disputed.
2. "Later work by González-Díaz resolved the problem of quantum instability; at least for 2 dimensions. In his paper published in Physical Review D, Vol. 62, González-Díaz proposed considering closed, time-like curves. This refinement allows for multiply-connected spaces, closing the geodesic incompletemeness and satisfying quantum instability requirements." Likewise disputed.
3. "Recently Boris Volfson applied for and was issued a patent for a device he claims works just like an alcubierre drive." True but very misleading, since the mainstream view is that Volfson is a crank and that this patent was yet another example of bizzare patent issued for a "device" which has no chance of working.

The mainstream view is in fact that "warp drives" can most likely not be physically realized. I also point out that it would be very misleading to state (as various WP article state or have stated until I noticed and corrected them) that papers by Alcubierre and others give solutions to the Einstein field equation which exhibit "warp drive" like effects. In fact, these are Lorentzian spacetimes but they are in no sense "solutions" to the EFE. I know that there are many enthusiastic fans of "warp drives" out there, but please don't try to mislead WP readers about the scientific status of this concept. TIA---CH 19:39, 29 May 2006 (UTC)