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Positive Energy Warp Drive from Hidden Geometric Structures

arxiv.org

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Re: Positive Energy Warp Drive from Hidden Geometric Structures

#71

Post by gpderetta »

beervirus wrote: post #7
SmellTheGlove wrote: post #2

This sounds pretty amazing, but I also have no real idea what I'm reading. > A modest numerical analysis is carried out on a set of example configurations, finding total energy requirements four orders of magnitude smaller than the solar mass. Can someone smarter than me say whether this is within the (reasonable-ish?) realm of matter-antimatter reactions? Like Star Trek!? 4 orders of magnitude less than the sun's ma…

> 4 orders of magnitude less than the sun's mass does sound like a positive development - still a lot but less than before, right? That’s something like 10^43 joules. Still not achievable anytime soon.

Well, we went from theoretically impossible to merely practically impossible. (Only slightly tongue in cheek)

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#72

Post by postalrat »

IdiocyInAction wrote: post #47
jack_pp wrote: post #43

Earlier quoted context omitted.

Isn't there evidence starting to surface that we have actually detected alien contact?

You mean that UAP stuff? Occam's razor says this is probably some electronic countermeasure stuff by the US or something.

Occam's razor actually says that?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#73

Post by R0b0t1 »

godelski wrote: post #68
cletus wrote: post #39

The lesson we should really take here is the power of wishful thinking. People dearly want to believe in FTL travel. Without it, the Universe just seems so vast, empty and distant. The truth is it is and it isn't. It's only really that on our current time scales. Not to be a broken record (there's some new variation on some old idea like every week it seems), but I'm firmly in the camp that believes FTL isn't possibl…

> The macro evidence in that if FTL were possible it makes it that much more unlikely that we haven't detected starfaring life. I don't think this is a great argument. Even with FTL the galaxy (not universe) is huge. Let's just say you can go 2x (warp factor 1.25) it would still take more than 2 years to reach Alpha Centauri (our closest star, 4.37 lyr). Even at 8c (Warp 2) it would still take >6 months. At 100c it i…

I don't think it's fair to say "or immortality, or generational ships." You can make a one way trip, sometimes, but you can't meaningfully communicate. FTL is necessary or the universe is kind of boring on a grand scale.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#74

Post by postalrat »

api wrote: post #57

If FTL is possible (and engineerable) then the Fermi paradox becomes a serious problem. There "should" be aliens all over the place unless... (1) We are wrong about the nature of the universe and strong theism / creationism or the simulation hypothesis (which is the same thing more or less) are right. (2) Life or complex life are so phenomenally unlikely that we are literally the only example in the local galactic su…

Fermi's paradox does not depend on FTL travel.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#75

Post by saagarjha »

dleslie wrote: post #63
nine_k wrote: post #38

Earlier quoted context omitted.

AFAICT, GR is symmetric in relation of the direction of time, as are most other important physical theories. What may add the arrow of time is the second law of thermodynamics: a statistical evolution of a system is not symmetric. I wonder now how a violation of causality could either circumvent of contradict the second law.

It's not creating new energy, right? It reads to me like causality violating configurations simply move energy around time as we'd move mass through space.

The second law, like all physical laws, does not violate conservation of energy. However, reversing causality can cause the reversal of entropy, which is what the second law deals with.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#76

Post by emeraldd »

samplatt wrote: post #44
akiselev wrote: post #5

Earlier quoted context omitted.

The first paper detailing the Alcubierre drive required exotic particles with negative mass to achieve a spacetime bubble (soliton) which is an issue since particles with negative mass have never been observed. The next big paper figured out how to do it with regular matter and it brought the requirements down to the energy equivalent of four solar masses. That would put it squarely into the realm of a type II or III…

>It'd be able to enter warp once. ...why once? Are you assuming all matter+antimatter is destroyed in the single trip? If you have x amount of critical material, could you not warp for half the distance of the "fuel" in your "tank" and then come back? IANAPhyicist. I'm assuming that if we have the ability to contain and harvest energy from a matter/antimatter reaction then we also have the ability to stop it & start…

IANAPhyicist but if I understand what’s being said correctly the amount of energy necessary to create the warp bubble in the first place, would require converting something roughly the mass of Jupiter. So you’d twice that to “come back”. It sounds much more like surfing a wave that something that get’s turned on or off.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#77

Post by a1369209993 »

javajosh wrote: post #65
jlokier wrote: post #37

Earlier quoted context omitted.

No it isn't. The speed of light in SR is not really about light. It's just a good way to explain things. You can calculate the speed of light from other physical, measurable constants without using light (the permittivity and permeability of free space). Those you can measure with inductors and capacitors. So because those measurable physical behaviours are invariant in all reference frames under SR, it follows that…

c is defined. https://physics.nist.gov/cgi-bin/cuu/Value?c You don't have to measure c, or calculate it. The causal chain goes the other way - we assume c is invariant and define capacitance and inductance in terms of it (c, that is).

No, the meter is defined (as c times a certain number of seconds).

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#79

Post by nwallin »

TheDudeMan wrote: post #16
gary_0 wrote: post #9

What do the authors of these warp drive papers think will happen causality-wise when the proposed vehicle effectively moves faster than c? You can't do that without doing nasty things to your light cone[0] and effectively traveling into your own past. Is a prerequisite of entertaining the idea of a warp drive that we disregard causality? As far as I know, there aren't any plausible loopholes in General Relativity tha…

"effectively traveling into your own past" Can you explain how traveling faster than light leads to that? Perhaps you meant "observing your own past?"

Being able to send messages faster than the speed of light grants the ability to send messages to yourself in the past. [0] If you can send messages to yourself in the past all manner of causality goes out the window.

First of all, it gives you the ability to solve NP-complete problems trivially.

Step 1: you receive a message from yourself from the future. It explains the problem, gives you a potential solution. Let's say you ask yourself to solve boolean satisfiability, gives you the problem statement, and then a potential solution. You check the solution: If the possible solution is correct, you send yourself an identical message. If the solution is not correct, you send the next possible permutation of the answer. So if you sent yourself the possible solution TTFTFTTTFTFFTTTFTF, you send yourself TTFTFTTTFTFFTTTFTT. If there are no further possible permutations, then you send yourself a statement saying that the problem is not solvable. You've created a time paradox; a future in which you send yourself an incorrectly solution is logically inconsistent. The only consistent universes are the ones where you send yourself the correct solution or not-solvable, and all other universes (starting with the one where you sent yourself the message FFFFFFFFFFFFFFFFFF) collapse into the valid one.

https://en.wikipedia.org/wiki/Tachyonic_antitelephone

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#80

Post by visualradio »

gfodor wrote: post #19

There is the threshold where these theories rule in human plausible warp drives, and then there is the weaker threshold where these theories rule in that they should be taken as serious explanations for the alleged “advanced technology” demonstrated by UAPs. I wonder what we ought to expect to see from such a device as an observer if the geometric formulation here is correct, even if we can’t explain the energy manag…

> then there is the weaker threshold where these theories rule in that they should be taken as serious explanations for the alleged “advanced technology” demonstrated by UAPs

No, it doesn't really do anything to weaken the threshold.

If humans discover a method of warp travel which is then validated by peer review, this does not do anything to increase the reliability of claims made by the US Air Force concerning the existence and performance characteristics of UAPs.

The reliability of the later claims are limited by the fact that there is no independent observation and verification from non-military sources, and due to the fact that former USAF employees such as Richard Doty have claimed they were hired to fabricate and provide false information to independent UFO researchers as part of a domestic counter-intelligence operation.

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