Accidental Warp Bubble

[sevenperforce]

So, I’m a little skeptical. This guy has been working on the Alcubierre metric for a while now, and so I’m not entirely sure this wasn’t what he was already looking for. But regardless, it’s a cool possibility.

https://scifi.radio/2021/12/07/darpa-researchers-create-first-genuine-warp-bubble-by-accident/

Working with the Casimir force evidently caused the formation of stable positive and negative vacuum energy distributions, which would literally be a (tiny) warp bubble. I read the source article, which is peer-reviewed and offers a mechanism for testing, which is quite exciting.

This isn’t a vanity journal, is it?

[JoeSchmuckatelli]

36 minutes ago, sevenperforce said:

So, I’m a little skeptical. This guy has been working on the Alcubierre metric for a while now, and so I’m not entirely sure this wasn’t what he was already looking for. But regardless, it’s a cool possibility.

https://scifi.radio/2021/12/07/darpa-researchers-create-first-genuine-warp-bubble-by-accident/

Working with the Casimir force evidently caused the formation of stable positive and negative vacuum energy distributions, which would literally be a (tiny) warp bubble. I read the source article, which is peer-reviewed and offers a mechanism for testing, which is quite exciting.

This isn’t a vanity journal, is it?

Neat

Here's link to the pdf of the paper (hoping it works) for anyone interested in the source material.   Worldline numerics applied to custom Casimir geometry generates unanticipated intersection with Alcubierre warp metric (springer.com)

There's lots of pictures for people like me and formulae for you smart guys out there!

...

It reads like, "Hey, we think we found something cool - and think we have a way to test it - and we don't think its a totally bonkers idea... what do you other smart folks think?  Would this work, and can we get some funding for additional research?"

Quote

While the analysis results discussed above are encouraging for the project objective of attempting to measure the presence of structure in the negative vacuum energy density within a customized Casimir cavity, the implications of this particular predicted negative vacuum energy density distribution is quite intriguing for an altogether different reason. As it so happens, the structure of the field around the pillar in the two dimensional plot is qualitatively very similar to a plot of the negative vacuum energy density necessary for the Alcubierre warp metric

Quote

Now that the Alcubierre metric has been introduced and the critical elements have been identified and discussed, a comparison between the exotic matter requirements of the warp concept and the numeric worldline analysis results for the custom Casimir cavity may now be made.

Quote

If a difference in transit time were observed, this would be an empirical confirmation of the generation of a real nano scale warp bubble on a chip.9 To be clear, this would not be some simple analogue or proxy representation of a space warp phenomenon, rather it would be a genuine implementation of the idea in physical fact with observable consequences in the laboratory – just not in the dramatic form of a craft bound for a distant stellar destination.

(Emphasis added)

Quote

The analysis also showed a possible intersection with a model developed in the context of general relativity to understand how hyperfast stellar travel might be manifested mathematically. The qualitative correlation would suggest that a chip-scale experiment might be explored to attempt to measure a tiny signature illustrative of the presence of the conjectured phenomenon.

(Emphasis added)

 

Thanks @sevenperforce!

Edited December 10, 2021 by JoeSchmuckatelli

[cubinator]

I would be interested to see the micro-scale experiment conducted. We have an actual way to determine whether this thing would act like a warp bubble. Even if it does, I'm sure scaling it up enough to be much use would be another challenge entirely. 

The paper itself doesn't seem to overstep its boundaries, only claiming that a mathematically similar phenomenon has been predicted and that it could be tested in a lab. The first I heard about this was a pop-sci article claiming that a warp field had already been constructed, though, which is false. So keep an eye out for misinformation regarding this study.

[kerbiloid]

Everyone, who is making the electric counter rotate backwards, and thus consumes negative power, is risking that the negative energy added to the electric power network, would accidentally form a negative energy bubble and turn his appartment into an unexpected portal into another dimension, through which the extrareality invaders may come in.

[cubinator]

21 minutes ago, kerbiloid said:

Everyone, who is making the electric counter rotate backwards, and thus consumes negative power, is risking that the negative energy added to the electric power network, would accidentally form a negative energy bubble and turn his appartment into an unexpected portal into another dimension, through which the extrareality invaders may come in.

Spoiler

 

 

[RealKerbal3x]

It's still 41 years until First Contact Day, we have time to figure it out.

[kerbiloid]

Depends on what's the "year" close to the wormhole.

[K^2]

3 hours ago, cubinator said:

I would be interested to see the micro-scale experiment conducted. We have an actual way to determine whether this thing would act like a warp bubble. Even if it does, I'm sure scaling it up enough to be much use would be another challenge entirely. 

We already know that it won't behave like a warp bubble as necessary for FTL because that requires the net energy of the bubble + contents to be zero. While Casimir effect may allow for creation of negative energy density regions, it is heavily energy-positive overall. 

There could be some other interesting uses for this effect, but in that case, similarities to Alcubierre metric are purely incidental. Of course, confirming negative energy density at all would be a great step forward, and the fact that simulations are being done to make predictions which can hopefully be turned into testable predictions in the future is all a good thing. This just isn't the breakthrough the article tries to present it as.

[insert_name]

Tldr the warp drive paper was from the same guy as the EM drive, and all he definitely proved was that the potential curves between his apparatus and the warp drive are a similar shape.

https://bigthink.com/starts-with-a-bang/no-warp-bubble/

[JoeSchmuckatelli]

10 hours ago, sevenperforce said:

This isn’t a vanity journal, is it?

Well, according to the author of the paper linked to by @insert_name it was "published in the open access (but often dubious) European Physical Journal C,"

[sevenperforce]

3 hours ago, JoeSchmuckatelli said:

Well, according to the author of the paper linked to by @insert_name it was "published in the open access (but often dubious) European Physical Journal C,"

I have a great deal of respect for Ethan, so I trust him, but I have not been able to independently verify the dubiosity (is that a word, or is it dubiousness??) of EPJC.

That being said, Dr. White's prior...activities...leads me to treat everything he says with a grain of salt.

7 hours ago, K^2 said:

There could be some other interesting uses for this effect, but in that case, similarities to Alcubierre metric are purely incidental. Of course, confirming negative energy density at all would be a great step forward, and the fact that simulations are being done to make predictions which can hopefully be turned into testable predictions in the future is all a good thing.

This paper is at the very limits of my understanding of physics (despite my degree therein), but from what I was able to glean, they were able to establish a stable, non-spherically-symmetric negative energy distribution using the Casimir interaction and associated mechanisms. If that's true, that's awesome. And it would be fairly easy (relatively or relativistically speaking) to confirm superluminal signal transfer using such a system.

This is not a "warp bubble" per se but if true, it's enough to say yes, this is something we can work with.

 

[JoeSchmuckatelli]

1 hour ago, sevenperforce said:

Dr. White's prior...activities...leads me to treat everything he says with a grain of salt

That whole EM drive thing was fun, tho.  Copper rocket?  Very SteamPunk.

I wonder, however, given both his prior NASA and DARPA history if he might, occasionally, touch on something functional.  Would certainly be cool if this thing pans out.

WHile there is criticism of the paper and publication - at least he's publishing (meaning peers can review) rather than dumping sciency stuff into the blogosphere.

 

[K^2]

On 12/10/2021 at 9:27 PM, sevenperforce said:

This paper is at the very limits of my understanding of physics (despite my degree therein), but from what I was able to glean, they were able to establish a stable, non-spherically-symmetric negative energy distribution using the Casimir interaction and associated mechanisms. If that's true, that's awesome. And it would be fairly easy (relatively or relativistically speaking) to confirm superluminal signal transfer using such a system.

These are not directly related. Simply having regions of negative energy density doesn't let you send signals at FTL speeds.

The way Alcubierre warp works is that you start out by crafting a space-time metric that gives you FTL transfer. You do so by simply writing out a metric that remains "at rest" with respect to the bubble as it accelerates and decelerates. Alcubierre chose to make metric both inside and outside of the bubble flat. The interior metric being flat isn't really critical - it's just a simplification. The exterior metric must be flat, because otherwise, the bubble will radiate gravity waves as it accelerates and worse, will produce something similar to Cherenkov radiation if it goes FTL, collapsing the bubble. This is why the net energy of the ship under warp must be zero. There are other ways to demonstrate it from conserved current as well. Now, this immediately tells you that some regions of negative energy must exist in the bubble walls. In Alcubierre's paper, the interior of the bubble is empty, and if you do the math, you do, indeed, find that the total energy of the bubble is zero, allowing it to be superluminal.

Crucially, it's the bubble that carries the contents in Alcubierre metric. So you have to have an ability to accelerate the bubble itself to superluminal speeds. Because Casimir effect is related to cavities in a conductor, in order for the bubble to accelerate, the conductor body must accelerate as well. And the negative energy generated is laughably small compared to the mass energy of the conductor. Meaning you can't possibly use Casimir effect for FTL travel via Alcubierre mechanism. There is no way to generate enough negative energy to compensate for the mass of the drive with Casimir effect alone.

There are some other suggestions that might allow use of Casimir effect for FTL. For example, negative energy density is necessary to create a traversable wormhole, including the kind that allow for time travel. In that case, the throat of the wormhole does not have to be traveling at superluminal speeds, and can, therefore, be stabilized by Casimir effect. Maybe. Nobody has ever worked out the correct configuration to confirm that it can actually be done. However, stabilizing the throat is just one part of the problem with wormholes. A wormhole is a topological construct, not just geometrical one, and we have neither found a way to alter topology of space-time, nor discovered any naturally existing wormholes that we could "shape" into a traversable one. So this remains deeply hypothetical.

But more importantly, none of these other ideas relate at all to this paper. All this paper has found is that Casimir effect may create a negative energy distribution that happens to be similar in shape to that required for Alcubierre drive, without matching any of the other requirements, nor having a possibility to match these requirements. It's also worth noting that there are assumptions going into the computation that have not been verified. The very idea that Casimir effect creates regions of negative energy density is still being debated, and to date, no experiment has confirmed negative energy densities directly. This paper might pave the way to a confirmation, if we can, for example, design an interferometry experiment that confirms predictions of the computations being used in this paper. But this is still work that needs to be done, and whether it is a step towards FTL or any kind of propulsion remains unknown.

[mikegarrison]

On 12/10/2021 at 9:27 PM, sevenperforce said:

That being said, Dr. White's prior...activities...leads me to treat everything he says with a grain of salt.

There are certain scientists and engineers who specialize in highly speculative physics and technology. IMO this is OK, because there is the remote possibility they might actually find something. Certainly we have seen crazy ideas like continental drift and special relativity turn out to be experimentally verified. On the other hand, the more speculative the ideas, the less likely it is that they will actually turn out to be correct.

It's like playing the lottery. The longer the odds, the bigger the prize. But also, the more losers. And the more chance that any individual ticket is a loser.

Edited December 12, 2021 by mikegarrison

[Exoscientist]

 Here’s an article on a different peer-reviewed published proposal for a warp drive,  This one remarkably does not require negative energy:

 

Star Trek’s Warp Drive Leads to New Physics
Researchers are taking a closer look at this science-fiction staple—and bringing the idea a little closer to reality
By Robert Gast, Spektrum on July 13, 2021
https://www.scientificamerican.com/article/star-treks-warp-drive-leads-to-new-physics/

 

  Robert Clark

 

 

Edited December 16, 2021 by Exoscientist

[JoeSchmuckatelli]

8 hours ago, Exoscientist said:

 Here’s an article on a different peer-reviewed published proposal for a warp drive,  This one remarkably does not require negative energy:

 

Star Trek’s Warp Drive Leads to New Physics
Researchers are taking a closer look at this science-fiction staple—and bringing the idea a little closer to reality
By Robert Gast, Spektrum on July 13, 2021
https://www.scientificamerican.com/article/star-treks-warp-drive-leads-to-new-physics/

 

  Robert Clark

 

 

"This is research at the fringe of science: not necessarily wrong but spiced with a large pinch of optimism." 

That's a great line! 

 

 

(-from the article)