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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

#41

Post by nikofeyn »

JoeAltmaier wrote: post #8
jaequery wrote: post #6

When ever I think of traveling through a wormhole/blackhole, I imagine you would be squished and crushed and come out the other end as pure vaporized energy. This makes me wonder, if there is the potential for our beings (or things) be able to be vaporized and then recreated to original form. If we are just mass and particles, this should be possible?

Its all about information. The order of atoms to make a person is information. No information passes thru the event horizon of a black hole. So, no.

> No information passes thru the event horizon of a black hole.

that is only true in one direction though, right?

Re: Travel through wormholes is possible, but slow

#42

Post by jbob2000 »

dosy wrote: post #24
jbob2000 wrote: post #22

Earlier quoted context omitted.

We would know. Either the secret space program requires enough exotic materials and science that you wouldn't be able to hide it OR it doesn't require that, so it's simple enough that any one of us could stumble upon it. Trillions of dollars vanished because humans are probably more greedy than they are curious.

governments can't keep secrets fallacy. they can. Manhattan. these days, you can just take people's phones.

The internet and prolific camera ownership wasn’t a thing back then.

Re: Travel through wormholes is possible, but slow

#43

Post by ben_w »

logfromblammo wrote: post #35
philipov wrote: post #3

Earlier quoted context omitted.

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…

So... Two entangled wormhole apertures function as Star Trek style transporter pads. Feed mass into one hole, scanning it as it goes in. Transmit the pattern to another aperture of the hole, using electromagnetic energy at the speed of light, and when that end ejects a mass, apply the pattern to it, so it resolves into an exact copy of what you put in. The distance the mass travels may be shorter than the distance th…

I don’t think the suicide booth model of a teleporter fits a quantum teleporter model, only the 3D printer teleporter model. From a quantum point of view, all (e.g.) electrons are indistinguishable excitations in the same field, and it’s the pattern that makes you “you”. If you’ll forgive a bit of poetic licence, quantum teleportation seems more like Discworld magic, where you have to exchange two identical sized lumps of matter.

Re: Travel through wormholes is possible, but slow

#44

Post by 0xffff2 »

dosy wrote: post #24
jbob2000 wrote: post #22

Earlier quoted context omitted.

We would know. Either the secret space program requires enough exotic materials and science that you wouldn't be able to hide it OR it doesn't require that, so it's simple enough that any one of us could stumble upon it. Trillions of dollars vanished because humans are probably more greedy than they are curious.

governments can't keep secrets fallacy. they can. Manhattan. these days, you can just take people's phones.

Every space launch and every large object in orbit are trivially observable. Even when the NRO launches top secret spy satellites that they barely acknowledge the existence of, we know exactly when the launch is. Thanks to the cold-war risk of nuclear ICBMs, every launch is publicly announced to reduce the risk of false positives in an early warning system.

In light of this, your proposition is impossible without also supposing the organization backing this hypothetical operation also has the ability to perfectly suppress all information related to the project. Literal back yard astronomers would notice every single launch, and every single "spy satellite" that disappeared off into space if the launches were announced but the payload kept secret.

You're basically speculating that there exists an organization capable of perfectly controlling all information worldwide. If that were true, there's hardly any point in worrying about it. In such a situation, we could be living in the Matrix for all we know and there really wouldn't be anything we could do about it.

Re: Travel through wormholes is possible, but slow

#45

Post by lloeki »

logfromblammo wrote: post #35
philipov wrote: post #3

Earlier quoted context omitted.

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…

So... Two entangled wormhole apertures function as Star Trek style transporter pads. Feed mass into one hole, scanning it as it goes in. Transmit the pattern to another aperture of the hole, using electromagnetic energy at the speed of light, and when that end ejects a mass, apply the pattern to it, so it resolves into an exact copy of what you put in. The distance the mass travels may be shorter than the distance th…

This sounds like the science-fiction version of a cryogenic scam.

Re: Travel through wormholes is possible, but slow

#46

Post by ben_w »

nikofeyn wrote: post #41
JoeAltmaier wrote: post #8

Earlier quoted context omitted.

Its all about information. The order of atoms to make a person is information. No information passes thru the event horizon of a black hole. So, no.

> No information passes thru the event horizon of a black hole. that is only true in one direction though, right?

From the point of view of something falling in you are correct.

From the point of view of something further away watching the thing falling in, it takes forever. I think. Time dilation is easy to lose track of.

Re: Travel through wormholes is possible, but slow

#47

Post by Filligree »

FakeComments wrote: post #31
eigenschwarz wrote: post #17

Earlier quoted context omitted.

The Average Null Energy Condition (ANEC) makes it so there can not be a traversable wormhole joining two otherwise disconnected regions of spacetime. So by construction, any infinite null geodesic (a light ray) which makes it through the wormhole must be chronal (causally connected). This means there can be no traveling faster than light over long distances by going through one.

You don’t really explain how the assumption leads to the conclusion — and I’m left with the impression you used many words to say “they just assumed you can’t”. Could you elaborate? Edit: Looking into energy conditions further, they are literally assumed restrictions on the equations because physicists felt some predictions were unphysical. I’d really like if someone could explain if there’s any justification to what…

Without negative matter, it's impossible to build a wormhole that's shorter than the distance through normal space.

This piece of math shows that it may still be possible to build a wormhole which isn't shorter than that distance. Obviously that wouldn't be much of a shortcut, but the potential research and (maybe) real-world applications are still impressive.

Re: Travel through wormholes is possible, but slow

#48

Post by FakeComments »

Filligree wrote: post #47
FakeComments wrote: post #31

Earlier quoted context omitted.

You don’t really explain how the assumption leads to the conclusion — and I’m left with the impression you used many words to say “they just assumed you can’t”. Could you elaborate? Edit: Looking into energy conditions further, they are literally assumed restrictions on the equations because physicists felt some predictions were unphysical. I’d really like if someone could explain if there’s any justification to what…

Without negative matter, it's impossible to build a wormhole that's shorter than the distance through normal space. This piece of math shows that it may still be possible to build a wormhole which isn't shorter than that distance. Obviously that wouldn't be much of a shortcut, but the potential research and (maybe) real-world applications are still impressive.

That’s not what I was asking.

I was asking about the particular usage of the average null energy condition as justification to rule out wormholes: why isn’t that just begging the question by assuming your conclusion? and how does that particular assumption actually lead to the conclusion there can’t be wormholes?

It’s interesting the downvotes for asking someone to support a scientific claim, and be clear where they’re making assumptions versus reaching empirical conclusions.

Re: Travel through wormholes is possible, but slow

#49

Post by Retra »

nikofeyn wrote: post #41
JoeAltmaier wrote: post #8

Earlier quoted context omitted.

Its all about information. The order of atoms to make a person is information. No information passes thru the event horizon of a black hole. So, no.

> No information passes thru the event horizon of a black hole. that is only true in one direction though, right?

There is only one direction through the event horizon of a black hole.

Re: Travel through wormholes is possible, but slow

#50

Post by Filligree »

ben_w wrote: post #46
nikofeyn wrote: post #41

Earlier quoted context omitted.

> No information passes thru the event horizon of a black hole. that is only true in one direction though, right?

From the point of view of something falling in you are correct. From the point of view of something further away watching the thing falling in, it takes forever. I think. Time dilation is easy to lose track of.

It's a neat demonstration of the holographic principle. From the point of view of an outside observer, there's no difference between the surface of the black hole and its volume; they're two different ways to describe the same thing, of varying usefulness. Reaching the 'surface' of the event horizon is equivalent to reaching the infinite future of the hole.

However, you'd still be spaghetti.

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