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Positive Energy Warp Drive from Hidden Geometric Structures

arxiv.org

1–10 of 194 posts

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#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 mass does sound like a positive development - still a lot but less than before, right?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#3
I honestly thought this article was going to lead to something written by Charlse Stross.

I mean with lines like "A geometrical interpretation of the Eulerian energy is found, shedding new light on superluminal solitons generated by realistic energy distributions" I'm still not sure it wasn't...

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#4

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…

I think that's like 1/10th of Jupiter. Wasn't there a space drive that needed negative mass of about one Jupiter?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#5

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…

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 civilization (1 solar mass worth of energy is in the same ballpark as the amount a star puts out over its entire lifetime).

If this paper is correct, it brings the requirements down to a tenth of Jupiter's mass, which is probably somewhat achievable for a type I civilization. The Enterprise would be the size of a small gas giant to hold an equivalent amount of matter and antimatter. It'd be able to enter warp once.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#7

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.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#8
"Warp drives in Einstein's general theory of relativity provide a unique mechanism for manned interstellar travel. It is well-known that the classical superluminal soliton[0] spacetimes require negative energy densities[1], likely sourced by quantum processes of the uncertainty principle. It has even been claimed by few that negative energy densities are a requirement of superluminal motion. However, recent studies suggest this may not be the case. A general decomposition of the defining variables and the corresponding decomposition of the Eulerian energy are studied. A geometrical interpretation of the Eulerian energy is found, shedding new light[2] on superluminal solitons generated by realistic energy distributions. With this new interpretation, it becomes a relatively simple matter to generate solitonic configurations, within a certain subclass, that respect the positive energy constraint. Using this newfound interpretation, a superluminal solitonic spacetime is presented that possesses positive semi-definite energy[3]. 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[4]. Extraordinarily, the example configurations are generated by purely positive energy densities, a tremendous improvement on the classical configurations. The geometrical interpretation of the Eulerian energy thus opens new doors to generating realistic warp fields for laboratory study and potential future manned interstellar travel."

0: Soliton - A "single bump" wave that propagates. See youtube for examples in water. These are (well-studied) solutions to the wave equation. In spacetime, we want some local "warp bubble" bump that is capable of moving/propagating around.

1: Negative energy density: Colloquially, this is like requiring negative mass. Nobody knows if this exists; most aren't hopeful.

2: Nice pun.

3: Positive semi-definite energy: I.e. non-negative (>=0)

4: So we're still talking mass-energies of Jupiter-(ish)-sized planets

This is very cool stuff. Definitely going to read the whole paper after work. Current questions:

- Is this really superluminal? Famously, the Alcubierre "warp bubble" solution doesn't actually propagate you superluminally unless you start it off that way.

- Is there a Minkowskian interior? The warped part of space is like your engine. We also need to have it carry around some flat space if we want it to be capable of carrying passengers.

- Can we construe this into PoC tests? How much energy do we need to detect warping (e.g. laser deflection) with current tech? Could some large-scale LIGO-like setup achieve detection?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#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 that allow you to pop up anywhere and anywhen you want in spacetime.

[0] https://en.wikipedia.org/wiki/Light_cone

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#10

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.

Progress in warp field research though has resulted in significant energy reductions though - everytime a more efficient formulation is found its a step on the way to a possible practical system.

After all, if it was easy then everyone would be doing it.

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