Positive Energy Warp Drive from Hidden Geometric Structures • Hacker News Board

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#151

Post by gradschool » Tue, Jul 13, 2021, 2:02 PM UTC

nine_k wrote: post #38

sigmoid10 wrote: post #15

Earlier quoted context omitted.

General relativity actually tells us nothing about whether causality is absolute. You can easily make up spacetime configurations that violate causality and still conform to general relativity. It's just that most people believe that causality should be protected, because... well it would be really weird if it wasn't. But it's just a conjecture and not like a theorem or anything.

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.

I would envision two chambers A and B connected by two vents X and Y, like Maxwell's demon but with two vents instead of one and both vents permanently open. Whereas X is an ordinary vent, Y has the property that any particle passing from A to B through it reaches B shortly before it leaves A. Any particle passing from B to A through Y disappears for a short time before reappearing in A. It seems to me that this setup would induce a current of air blowing from A to B through Y and from B to A through X, but I'm only an amateur and could be full of hot air myself.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#152

Post by WJW » Tue, Jul 13, 2021, 2:14 PM UTC

TrevorJ wrote: post #23

XorNot wrote: post #10

Earlier quoted context omitted.

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.

We've definitely achieved progress on this sort of scale with transistor density. Not that it's at all similar, but it's interesting to observe that we do seem to be able to occasionally bring things within our grasp that would have sounded absolutely silly a lifetime ago.

Did we though? From milli- to nanometers is "only" 9 orders of magnitude. 10^43 J is about 30 order of magnitude from practical application than the first transistor was. Also, warp bubble generation might be more like electric motors, which have gone from ~2% to ~95% efficiency and will never ever surpass 100%.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#153

Post by iflp » Tue, Jul 13, 2021, 2:19 PM UTC

hyperpallium2 wrote: post #61

godelski wrote: post #50

Everyone always talks about FTL travel for spacecraft, but there's also an interesting perspective from weapons side (and this a reason to be a bit careful and think about some ethics as we move along). A FTL kinetic weapon would be devastating. If it comes with a collapsing warp bubble then there's basically a gamma ray "gun" that travels right in front of your mass that is traveling at tremendous speeds. You look a…

If we're talking surprising applications of FTL, what about reducing latencies within CPUs?

If you are willing to assume CTC: https://www.scottaaronson.com/democritus/lec19.html

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#154

Post by 52-6F-62 » Tue, Jul 13, 2021, 2:43 PM UTC

native_samples wrote: post #116

jxf wrote: post #33

Earlier quoted context omitted.

The goal of warp drive is to produce a modified region of spacetime that makes it feasible to travel faster than light. There are an infinitude of different approaches. The authors in this paper find that if you impose specific constraints on the way the modified region of spacetime is shaped and evolves over time, you don't need the negative energy anymore. However, you do need a very high energy density, strong eno…

The sociology of this is fascinating. For my whole life I've heard that travelling faster than light is not only impossible, but so obviously absurdly impossible that only loons and sci-fi writers bother to think about it at all. Now I'm reading that "There are an infinitude of different approaches" to the problem! What exactly is the breakthrough that has led to this recent spurt of warp drive papers? As far as I ca…

> The sociology of this is fascinating.

It really is.

It's not like these are entirely new questions, but they used to be relegated to much smaller circles.

Hell, even recall any theoretical physics notions in other threads on HN and watch it burn.

It definitely seems like a bit of a philosophical change is sweeping throughout society, and it's probably mainly do to the increased speed and spread of information. It's easy to ignore, but those who don't are sort of forced to revaluate their world view and even their understanding of reality.

We have mainstream philosophers and neuroscientists giving talks on the limits of our perceptions in language "lay" people can understand. It's an interesting time to follow these developments.

It's almost like a new-age open-mindedness without the woo-woo. It was probably never really true, but growing up it felt like the answers were all written, and the universe was sticks and stones and the suggestion of anything else was nonsense. It seems more open now, and more intellectually encouraging, isn't it?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#155

Post by gfodor » Tue, Jul 13, 2021, 3:12 PM UTC

visualradio wrote: post #80

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…

You're not understanding what I am saying. Also the US Air Force is explicitly not involved in the latest disclosure regarding UAPs, so I suspect you're not fully up to date on everything.

My point is that if a theoretical model for a warp drive emerges that provides falsifiable hypotheses in terms of what an external observer ought to see, this could be a useful tool for scientists to use if/when they are given the underlying UAP data I expect to see the government hand over the next 12-18 months.

The threshold I am referring to is when the theory becomes cohesive enough to provide such a tool for being able to generate such explanations, as opposed to the threshold where it could lead to actual applied physics.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#156

Post by jjk166 » Tue, Jul 13, 2021, 3:29 PM UTC

godelski wrote: post #50

Everyone always talks about FTL travel for spacecraft, but there's also an interesting perspective from weapons side (and this a reason to be a bit careful and think about some ethics as we move along). A FTL kinetic weapon would be devastating. If it comes with a collapsing warp bubble then there's basically a gamma ray "gun" that travels right in front of your mass that is traveling at tremendous speeds. You look a…

If you can twist the mass of jupiter into a bubble and accelerate it to lightspeed, you probably already have the means to destroy an earth-like planet.

This is like a medieval person cautioning against the development of jet engines due to how fast they could make a catapult swing.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#157

Post by cowboysauce » Tue, Jul 13, 2021, 3:39 PM UTC

prox wrote: post #139

phendrenad2 wrote: post #122

Earlier quoted context omitted.

So we're traveling away from one another at 0.9c. I send a paper airplane in your direction at 500x the speed of light. You receive it and send it back (at 500c). Does it not arrive before I sent it, from my perspective?

Does this reverse time though? 0.9c is 90% of lightspeed, and for the sake of your example, 500c is just instantaneous. If light is just information, wouldn’t it just be a matter of seemingly getting something very fast?

If you're traveling at 0.9c then there will be significant time dilation. Since velocity is relative, both parties will see each other as severely time dilated which can lead to somebody receiving a reply to a message before they send it.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#158

Post by effingwewt » Tue, Jul 13, 2021, 3:40 PM UTC

effingwewt wrote: post #104

godelski wrote: post #92

Earlier quoted context omitted.

I wouldn't say primary plot of Ender's Game. I'd say it was a higher focus in Speaker for the Dead. Still, the device is used in a lot of Sci-Fis. Card wasn't even the first to use the term Ansible, though he did use that exact word.

It was most definitely one of if not the most central plot point of the series. Not sure how far you got, but the entire series including the prequels is worth a read imho.

Dropped by to see what was up, only a drive-by downvote so let me explain since you didn't.

Its becomes clear by the end that the ansibles being used were creating philotic threads throughout the universe. So the very thing they had been using for FTL communication was building a huge network. This allowed them to not only save the trees by uploading them, it akso allowed Ender to be brought to no-space where he was able to subconsciously create young Peter and Valentine.

So, they ended up being central to the entire story.

You're welcome.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#159

Post by mr_gibbins » Tue, Jul 13, 2021, 3:52 PM UTC

dougmwne wrote: post #150

native_samples wrote: post #114

Earlier quoted context omitted.

Star Trek's tech vision is astounding. How many things in it have actually been built? I count: • Tablets (the padds) • VR "holodecks" • Computers that you can talk to and ask questions • "Tricorders" (smartphones?) • Turbolifts ( https://www.dezeen.com/2017/07/12/thyssenkrupp-unveils-world... ) Maybe we'll get to add a warp drive to the list by the time I die. What else?

Walking around with the sum total of human knowledge. That featured heavily in a lot of episodes where the ship carried around a library of everything and and could communicate back to the network on Earth for everything squared. Often problems were solved by database search algorithm. And the VR Holodeck is spot on actually. I was having moments where I was questioning how much better the experience really would be…

We used to have the sum total of human knowledge, or at least a good facsimile of it. Unfortunately, with the Internet as we know it transformed into a handful of walled gardens, finding detailed knowledge is increasingly difficult.

Wikipedia is excellent, as usual. But it is an encyclopaedia, not a definitive source of original knowledge, and it remains the case that I can browse my modest (physical) bookshelves and find a book on, say, Russian modern history that will give me far more in-depth information in the first ten pages than I can find online. Same applies for almost any genre, except perhaps fiction. Seven Years In Tibet taught me more about Tibetan geography and culture than any amount of Googling could do.

The idea of an infinite knowledge bank is appealing and I think the Internet could have made it - imagine a suite of applications that complement Wikipedia - but commercialism has ruined the utopia, as it is designed to do.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#160

Post by dleslie » Tue, Jul 13, 2021, 4:08 PM UTC

saagarjha wrote: post #75

dleslie wrote: post #63

Earlier quoted context omitted.

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.

I don't believe it reverses entropy, if we consider the entire system to include all of time.

Moving energy around through time may serve to increase entropy overall.