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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

#121

Post by Johnny555 »

noobermin wrote: post #71

I'm not sure if this is the researchers' issue or is an issue with the scientific press, but it would help if the "discoveries" theorists made with their hitherto unestablished and untested theories like various string and QG based theories were not touted as discoveries about the real world.

I think for anyone for whom this theory is at all relevant, it's already clear that this is a theory, not a proven fact.

The fact that its theoretical is mentioned in the article for anyone that bothered to read past the first few paragraphs. For the rest of us, it just makes for interesting party conversation whether the theory pans out or not (which couldn't be proven by actually transiting a wormhole within any of our lifetimes)

So no harm, no foul -- anything that makes theoretical science interesting in the popular press is a win in my book.

Re: Travel through wormholes is possible, but slow

#122

Post by muxator »

krastanov wrote: post #117
noobermin wrote: post #71

I'm not sure if this is the researchers' issue or is an issue with the scientific press, but it would help if the "discoveries" theorists made with their hitherto unestablished and untested theories like various string and QG based theories were not touted as discoveries about the real world.

"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…

Came here to (wrongly) correct your statement, as I remembered that the only relevant effect was from special relativity.

It turns out it is the exact opposite: general relativity effects prevail [0]. Thanks for forcing me to check!

> Special Relativity predicts that the on-board atomic clocks [...] should fall behind clocks on the ground by about 7 microseconds per day [...] due to the time dilatation effect of their relative motion.

> Further, the satellites are in orbits [...] where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly [...]. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.

> The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!

[0] http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps....

Re: Travel through wormholes is possible, but slow

#123

Post by virgilp »

TotempaaltJ wrote: post #107
jcoffland wrote: post #77

Earlier quoted context omitted.

Shadows can move faster than light.

That's an interesting assertion... Why would shadows be able to move faster than light?

It's perfectly correct and does not contradict physics. Think about it in the opposite direction - say you have a perfect laser, with perfect pointing ability. You pick two planets that are far away from each other but at roughly the same distance from Earth, and make an angle of 10 degrees with it; it will take you a few seconds to "move" the laser 10 degrees and thus move the spot from one planet to the other - in the process making the spot "travel" millions of light years in a few seconds. However, the light itself has not traveled at faster-than-light speeds (it still takes a lot of years for the light from your laser pointer to reach any one of those two planets).

Re: Travel through wormholes is possible, but slow

#124

Post by hinkley »

olemartinorg wrote: post #113
hinkley wrote: post #105

Earlier quoted context omitted.

I'm kind of relieved by this. The last wormhole conversation I had with someone, I imagined a weapon using a short-distance wormhole with the ends opposed 180 degrees, and using a star's own gravity to tear chunks out of it. Everybody dies from massive solar flares. Of course time travel books, wormhole researchers, and myself all make the same mistake over and over: If you made a wormhole or traveled in time, why do…

Presumably, if you're smart enough to make a time machine, you'd be smart enough to calculate the target position in both time _and_ space.

I suspect if you had that much understanding of orbital mechanics, you'd be a billionaire already and not worry so much about time travel.

Re: Travel through wormholes is possible, but slow

#125

Post by stcredzero »

p1esk wrote: post #111
nkrisc wrote: post #103

Earlier quoted context omitted.

Perhaps it's because building a giant ship that can carry countless generations of inhabitants many light years is really more of just an engineering problem. All the challenges (of which there are plenty) all have reasonably known solutions. There's not really all that much novel technology required. Just better tech than we have, and a lot of it, to be sure. Uploading a consciousness into a computer and have it rem…

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 lossy compression" of the human race?

Re: Travel through wormholes is possible, but slow

#126

Post by Zardoz84 »

pontifier wrote: post #101
lupire wrote: post #75

Earlier quoted context omitted.

Uncertainty principle says...probably not. It's impossible to make a complete copy of the pattern. Even aside from that -- it's unlikely to be practical to scan something down to the smallest level level of matter, because the tools we use to manipulate things can't manipulate things smaller than their own finest details. So there's a "glass wall" in that you can only replicate things less finely detailed than the re…

That's what the "Heisinberg compensators" in star trek fix. I heard this phrase in an episode once, and decided to figure out how that could even work... What I came up with was the idea that the scanning stage doesn't need to gather exact data because it really doesn't matter. You just need to get averages, and then build up a model that matches the statistics... (you don't need to discover the exact energy and mome…

"Heisinberg compensators" it's a clever lie that La Forge uses to fool Moriarty on a chapter.

Re: Travel through wormholes is possible, but slow

#127

Post by amelius »

throwawaymath wrote: post #116
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.

If you are okay with that, you no longer need to upload anything, and your problem becomes one of imitation rather than continuity. You can dispense with the philosophical question of identity entirely and obviate away the problem of interfacing with a mind. Find a way to decompose an individual's personality into progressively more granular dimensions of behavior. Model stimulus -> response reactions as transformati…

This assumes that the entire state space of a human's mind is observable.

Some (most?) people have a rich internal world which can never be caught by looking at I/O relations.

Also, do you believe that by asking e.g. a person like Albert Einstein a reasonable amount of questions (an amount that a person can answer without getting seriously annoyed or fatigued), you would be able to reconstruct their problem solving skills? Sounds unlikely to me.

Re: Travel through wormholes is possible, but slow

#128

Post by andrewflnr »

hinkley wrote: post #105
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.

I'm kind of relieved by this. The last wormhole conversation I had with someone, I imagined a weapon using a short-distance wormhole with the ends opposed 180 degrees, and using a star's own gravity to tear chunks out of it. Everybody dies from massive solar flares. Of course time travel books, wormhole researchers, and myself all make the same mistake over and over: If you made a wormhole or traveled in time, why do…

AIUI wormhole mouths don't have a direction. They're spherical.

The picture of a wormhole as a bell-shaped indentation in a sheet, like the graphic on this article, is an artifact of trying to explain 4-d concepts in 3-d shapes (in 2-d images). For a being in the 2-d sheet, the wormhole is a circularly symmetric spot of weird-shaped space. In real 3-d space, a wormhole is a spherically symmetric spot of weird-shaped space.

Re: Travel through wormholes is possible, but slow

#129

Post by craftinator »

earenndil wrote: post #109
BartBoch wrote: post #69

Earlier quoted context omitted.

Well, we are able to research FTL for only a few decades. Give it a few more due to complexity. Few ages ago people thought that the world is flat... Also, there are theories of FTL: https://en.wikipedia.org/wiki/Faster-than-light

> Few ages ago people thought that the world is flat... Ah, no they didn't. Scientific consensus has been the earth is round for thousands of years.

As the word 'age' is used in the original comment, a likely synonym is 'millenia', so you are in aggreement with the poster.

Re: Travel through wormholes is possible, but slow

#130

Post by dfox »

throwawaymath wrote: post #116
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.

If you are okay with that, you no longer need to upload anything, and your problem becomes one of imitation rather than continuity. You can dispense with the philosophical question of identity entirely and obviate away the problem of interfacing with a mind. Find a way to decompose an individual's personality into progressively more granular dimensions of behavior. Model stimulus -> response reactions as transformati…

Modeling a mind as giant stimulus->response is similar issue as "breaking" an block cipher by building exhaustive input->output map, which for 256b blocks almost certainly requires more resources than is contained in whole known universe.

On the other hand while uploading minds probably has some issues, it involves replicating thing that we can assume resides in physical space, the question remains as to how and whether at all we can measure the internal structure with sufficient accuracy and whether such measurement is nondestructive.

And in the end, problem of somehow interfacing with an mind can mean many things which range from solved issue (when typing this comment counts as "interfacing") to something that for me seems like purely engineering issue (building new neural attached "peripherals" for the brain or emulating existing ones)

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