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Travel through wormholes is possible, but slow

phys.org

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Re: Travel through wormholes is possible, but slow

#161

Post by Robotbeat »

nine_k wrote: post #81
piker wrote: post #51

Earlier quoted context omitted.

So that's it, then? Some thing, say, a million light years away from another thing is in practice entirely inaccessible to civilizations existing on that other thing, requiring a minimum of a million years to reach?

This depends on what do you mean by 'inaccessible'. Going there and back again, and telling your pals how things are 1000LY away is likely impossible. Expanding your civilization to more and more habitable celestial bodies, slowly but relatively surely, is entirely possible. This is how e.g. plants colonize vast spaces, being limited by the speed of their growth often by inches per lifetime. (You should also consider…

Extending human lifespan (perhaps using methods of hibernation, perhaps not) is easier technologically than basically any viable form of crewed interstellar travel.

Re: Travel through wormholes is possible, but slow

#162

Post by p1esk »

stcredzero wrote: post #125
p1esk wrote: post #111

Earlier quoted context omitted.

Or we can relax the requirement that “it remains you”, and be content with the idea of cloning the mind. This should be somewhat easier to achieve.

Or we can relax the requirement that “it remains you”, and be content with the idea of cloning the mind. How do we know that the incomprehensibly weird and advanced minds running our ships and habitats in those unimaginably distant points of space and time won't just decide that virtual smiley faces with our names written on them are close enough to, "it remains you." How do we know they won't one day do a "slightly…

Not sure I follow, which "incomprehensibly weird and advanced minds"? Our minds after cloning?

Re: Travel through wormholes is possible, but slow

#163

Post by Terr_ »

philipov wrote: post #3
SketchySeaBeast wrote: post #2

Can someone point out where the article says why it's slower? I'm having difficulty unpacking: "The new theory was inspired when Jafferis began thinking about two black holes that were entangled on a quantum level, as formulated in the ER=EPR correspondence by Juan Maldacena from the Institute for Advanced Study and Lenny Susskind from Stanford. Although this means the direct connection between the black holes is sho…

Based on the colloquia I watched by Lenny Susskind, the problem is that you can put something into a wormhole, but to get it out the other end, you have to carry the encoding you get to the other end of the wormhole to decode the output. Because the distance to the singularity grows at the speed of light, the length of the wormhole is essentially infinite. It is only the operator you get from putting the object into…

> the problem is that you can put something into a wormhole, but to get it out the other end, you have to carry the encoding you get to the other end of the wormhole to decode the output.

That sounds a lot like how entangled particles can't be used to communicate faster than light.

While you can make observations immediately, you can't turn them into useful information about the other end, at least not until you get missing data which has to reach you by normal means.

Hence the focus on using entangled particles as a kind of tamper-detector or "reusable random one-time pad", rather than for transmitting information.

Re: Travel through wormholes is possible, but slow

#164

Post by stcredzero »

p1esk wrote: post #162
stcredzero wrote: post #125

Earlier quoted context omitted.

Or we can relax the requirement that “it remains you”, and be content with the idea of cloning the mind. How do we know that the incomprehensibly weird and advanced minds running our ships and habitats in those unimaginably distant points of space and time won't just decide that virtual smiley faces with our names written on them are close enough to, "it remains you." How do we know they won't one day do a "slightly…

Not sure I follow, which "incomprehensibly weird and advanced minds"? Our minds after cloning?

I left it up to the imagination of the reader. It could be one of our minds after an imperfect cloning, modified by someone for "efficiency." It could be super-optimizing AIs. Tens of thousands of years from now, thousands of light-years distant, who knows what it will be like?

Re: Travel through wormholes is possible, but slow

#165

Post by m4rtink »

svnpenn wrote: post #32
chrxr wrote: post #20

Earlier quoted context omitted.

The philosophical implications of this are the subject of one of my favorite web-comics: The Machine, from Existential Comics http://existentialcomics.com/comic/1

https://wikipedia.org/wiki/The_Jaunt https://wikipedia.org/wiki/White_Christmas_(Black_Mirror)

What these two stories describe would surely be hell for a normal human and likely also equivalent AI consciousness.

On the other hand, if you could run even a simple computer program in such a context, it opens interesting possibilities. In "The Jaunt" they describe some of the periods lasting up to billions of years - imagine you could keep a simple algorithm (say prime factorization) running for that long, without the associated energy costs and get the results instantaneously from your point of view.

BTW, of course people from Orions Arm have put together something similar but actually remotely physically plausible using a concept called "Tipler Oracle": https://orionsarm.com/eg-article/48507a11adbd7

Re: Travel through wormholes is possible, but slow

#166

Post by [deleted] »

simias wrote: post #63
dosy wrote: post #52

Earlier quoted context omitted.

unnecessary. visual cloaking. are you watching objects in 5th gen FLIR? zero radar cross section. even USAF has acknowledged craft you can't trivially observe. your point is rubbish.

This way of talking (using very short nominal sentences, citing many more or less related next to one another) seems very common among conspiracy theorists. I genuinely wonder where that comes from and if it's a conscious choice or some memetic imitation.

[deleted]

Re: Travel through wormholes is possible, but slow

#167

Post by dosy »

0xffff2 wrote: post #74
dosy wrote: post #52

Earlier quoted context omitted.

unnecessary. visual cloaking. are you watching objects in 5th gen FLIR? zero radar cross section. even USAF has acknowledged craft you can't trivially observe. your point is rubbish.

You seem to be assigning the capabilities of stealth aircraft to space launches. The energies involved are radically different. There is absolutely no evidence whatsoever that anyone has anything even approaching the technology needed to conduct an undetectable orbital launch. Again, I'd refer to the well-publicized launches of top secret NRO payloads. If the US government could launch those payloads without telling…

orbital launch energy takes so much because you have to overcome gravity. recorded maneuvers of these Craft turning at thousands of miles per hour doing right angles indicates they don't have to care about gravity. so getting out of Earth's orbit shouldn't take so much energy besides there's never any heat signature or obvious propulsion system shown, so no it wouldn't show some trace if leaving. actually it's pretty crazy to convince yourself that something's crazy just because you don't want to think about it. you could just admit that the thought scares you and then start dealing with your feelings, that would be the sane thing to do.

Re: Travel through wormholes is possible, but slow

#168

Post by thereisnospork »

krastanov wrote: post #159
pmiller2 wrote: post #156

Earlier quoted context omitted.

I'm not exactly sure which version of "If you can prove that all of those have to say the same thing...." you're arguing for. It doesn't scientifically matter what statements you can make about any number of mathematical constructs if none of those constructs make testable predictions. Remember, falsifiability is a necessary condition for a construct to be a valid scientific theory. OTOH, it does matter if you are ab…

Ah, I think we have a deep "philosophy of science" disagreement. Basically, it is not just "falsifiability", but also "probability" of being correct. Probability that can be informed by things like formal versions of Occam's razor (e.g. Kolmogorov complexity, Akaike information criterion, etc). Here are a few premises on which I based my statement (I will pick one particular venue of scientific research, so I will no…

> If both the math constraints and the interpretation of an experiment are based on the same assumption, why are you taking the interpretation of the experiment any more seriously than the pure math.

Because math models the experiment, it does not define it's results.

Even math as fundamental as the laws of thermodynamics does not constrain what is permitted; they are axioms which describe the universe as best we are able to view it. If all competing theories of quantum gravity agree on a point, it would mean almost[1] nothing until that point is observed.

From the outside it feels like there is a fallacy common in at least some branches of physics (string theory...) where over-fitting math is equated with insight.

[1]I suppose you could break out Bayes' theorem and try to work out a prior for comparable theories being wrong, degree of independence between theories, etc...

Re: Travel through wormholes is possible, but slow

#169

Post by mikekchar »

ketralnis wrote: post #134
krastanov wrote: post #117

Earlier quoted context omitted.

"Discoveries" about the mathematical structure of these theories are actually incredibly important even if no current day experiment can conceivably test them. Special and general relativity were discoveries made in this way (at least to an extent), and now general relativity is important for the proper functioning of technology as "trivial and boring" as GPS. Even earlier in our history, much of thermodynamics was d…

They're incredibly important, but they shouldn't be touted as facts until there's some consensus that they are facts

I think the key here is the word "fact". Scientific models are models. They are good models if they correspond with measurements that we make in the real world. The are even better models if they make a prediction that we can test in the real world. However, a model is never a "fact". "The FSM did it" is always going to be a possibility, even if it is an incredibly remote one.

We use scientific models because they are useful not because they are fact. Even if our model does not always match our observations it can still be a useful model in some circumstances. It's very important when talking about science that we understand that it isn't fact. It is a model. It might be a good model. It might be a bad model. It might be a useful model for our application. It might be a poor model for our application. That's it.

When you see a headline that says "X is Y" and it's about a scientific model, what that means is "If our model is consistent with the real world then the model predicts that we should find that X appears to be Y in the real world". But that's a bit too long to put in a headline and you would have to do it for every scientific conversation.

It is extremely unfortunate that on the first day of junior high school when you start doing "proper" science classes that they don't sit people down and explain what a scientific model is. Mostly I think it's because the teachers don't know, because their teachers never taught them.

Re: Travel through wormholes is possible, but slow

#170

Post by krastanov »

thereisnospork wrote: post #168
krastanov wrote: post #159

Earlier quoted context omitted.

Ah, I think we have a deep "philosophy of science" disagreement. Basically, it is not just "falsifiability", but also "probability" of being correct. Probability that can be informed by things like formal versions of Occam's razor (e.g. Kolmogorov complexity, Akaike information criterion, etc). Here are a few premises on which I based my statement (I will pick one particular venue of scientific research, so I will no…

> If both the math constraints and the interpretation of an experiment are based on the same assumption, why are you taking the interpretation of the experiment any more seriously than the pure math. Because math models the experiment, it does not define it's results. Even math as fundamental as the laws of thermodynamics does not constrain what is permitted; they are axioms which describe the universe as best we are…

Maybe a 100 years ago. With today's fundamental physics experiments (accelerators, non EM telescopes, and especially quantum foundations tests) the mathematical constructs are an inseparable part of the interpretation of the experiment.

And there it is hardly over fitting when the same results come from vastly different mathematical constructs.

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