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Travel through wormholes is possible, but slow

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131–140 of 190 posts

Re: Travel through wormholes is possible, but slow

#131

Earlier quoted context omitted.

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.

No sensible protagonist or villain use time travel to become a billionaire. There are usually better pursuits involved.

Re: Travel through wormholes is possible, but slow

#132

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…

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…

True. You could still use this to make two Lagrange points near the surface, mucking up everything. The fact that the hole has to be longer than the distance traveled would greatly reduce the gravitational field coming out of the hole.

You could still drop one end of the hole into the sun... (and I’ve just realized this was a Farscape plot and therefore how the idea got into my head in the first place)

Re: Travel through wormholes is possible, but slow

#133
post #84
post #76

Earlier quoted context omitted.

Well, theoretically they could load their civilization up on a giant ship and move their civilization there over the course of a million years. Likelihood of success? Probably not great, but possible.

Everyone is missing the obvious solution. If we're talking about tech this fantastical, the best idea is to ditch our ephemeral biological bodies, jump onto a synthetic medium, and call it a day. Hit pause so the journey takes a fraction of a second, or spend 1000Y in a VR - do whatever you want. I don't see a future where we're this advanced yet still content with our frighteningly fragile bodies.

Or better yet, do the "Contact" thing, and just transmit information. Start with something to generate interest. Then maybe some (hopefully appreciated) knowledge and/or technology. Then instructions for building VR or robots, and data to load them with.

Re: Travel through wormholes is possible, but slow

#134

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…

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

Re: Travel through wormholes is possible, but slow

#135

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 it goes beyond the scientific press. There seems to be a general tendency to squash the intricacies of anything and react impulsively to some red herring or whatever; such comments dominate all online forums I've ever seen.

Here is a fantastically interesting article that maybe has some new insight on the nature of spacetime; top comment on HN thread about it is some person loudly and incredibly pretentiously mistaking their own misunderstanding of the intricacies of 'truth' in science (and how there are different levels) for some flaw in the work itself.

You know, the underlying sentiment here is a good one. How do we know what we know, what do our theories really tell us, etc. All excellent questions. But you didn't express that at all, instead you say these things shouldn't be 'touted as discoveries about the real world.'

That's all you man! No theorist ever has wanted people to think this of their work, it slaughters the beautiful intricacies of it and leads to public relations disasters like this.

Don't go misunderstanding shit and then confidently be blaming it on other people man. Rhetoric matters.

The whole "it's just a theory" thing has done so much harm to public understanding and appreciation. It's an impossible starting point for a conversation, if you think "it's just a theory", you're not wrong, as much as entirely missing the point. How do you start with that and get to an understanding that things aren't always absolutely right or wrong, that contexts and assumptions matter, that things can be true in one setting (the math) and uncertain in another (the real world). That for most things what we are more than anything is uncertain. That there are many different kinds of uncertainty.

How are the subtle intricacies of things (that the answer to almost everything starts with "well, that depends...") supposed to survive forums where conversations are heavily selected for ability to grab attention? Not a rhetorical question, if you got ideas I want to hear them.

PS noobermin, I don't mean to be overly-critical of you although it sure sounds like it. I'm using 'you the pronoun'. Just something I think about a lot that you catalyzed me into trying to express...

Re: Travel through wormholes is possible, but slow

#136
post #81
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…

I get what you are saying, but it seems like the plant approach is mostly useless to humans. If the people on opposite sides of a galactic civilization are so far away that they cannot meaningfully interact, then it seems like that's no different than the other person not existing from their perspective.

Re: Travel through wormholes is possible, but slow

#137

Earlier quoted context omitted.

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…

There's two possible interpretations here. The implication of "shadows travel faster than light" is that information about the lack of light is faster. This interpretation is false. In your thought experiment, the information of the lasers moving still only travels at speed of light, even if the actual movement took only a fraction of that time. So the "shadow" on Earth reacts at the speed of light to changes in the source.

However, if the idea is that a laser that is continuously lit can "sweep" a path, such that the laser dot appears to move faster than light could travel that same path... Then of course that's trivially true. The light is traveling the radius of the arc, not the length.

Re: Travel through wormholes is possible, but slow

#138
post #46

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.

> 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.

This has always made me wonder that if this is true: "From the point of view of something further away watching the thing falling in, it takes forever." Then how does a black hole increase in mass from the pov of "something further away," as things fall into it? Is it just the light coming from the captured object that gets stopped in time, and the mass does get absorbed increasing the black hole's mass in a more normal time frame?

Re: Travel through wormholes is possible, but slow

#139
post #130

Earlier quoted context omitted.

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 whet…

I can see why you're drawing a comparison between enumerating stimulus -> response correspondences and "breaking" encryption using a lookup table. But I don't agree that the two would be comparable in difficulty a priori. First, encryption schemes typically try to complicate their linear structure by design, such that inverting the sequence of linear transformations can't be done without (ostensibly) secret information. Second, encryption schemes also approximate maximal randomness, which is entirely foreign to human activity.

For a basic example off the top of my head, consider a hash function. A hash function h : {0, 1}^' --> {0, 1}^n is not actually* injective (it can't be, since the domain is effectively infinite-dimensional and the codomain is finite-dimensional). However, cryptographic security mandates that it should be infeasible to find a preimage message for any digest in the codomain. Moreover messages with very small differences in the domain should be mapped to digests with very large differences in the codomain. This artificial noise and complexity doesn't resemble human reactions whatsoever; it's fairly easy to say two things which will each elicit your regional-specific greeting. In general many human responses have common triggers, and I would further conjecture that you could categorically simplify this further by reducing human responses to broader equivalence classes based on language, geographical region, mood, etc.

This is not to say it isn't challenging. I would expect building a linear approximation of a human mind using input -> output mappings to be extraordinarily difficult. But it's not artificially difficult, like well-designed cryptography. Breaking well-designed cryptography is intended to be, in a mathematical sense, a maximally difficult endeavor - much more difficult than basically anything else you can possibly do in nature.

More to my original point you and I can at least entertain a coherent conversation about building a matrix representation of a human mind using finite stimulus and response spaces. We're in familiar territory, even if it's not ultimately possible or feasible. It's mathematically sound to approach this, given a few well-defined assumptions.

In contrast, I don't know (nor am I confident anyone else knows) how to 1) replicate a human mind via as of yet nonexistent direct brain-interface technology, or 2) how to upload a human mind, using even more nonexistent technology so as to preserve continuity of consciousness. Not only are there rampant unknowns unknowns involved in the engineering efforts entailed here, there are unresolved questions and rampant philosophical disagreements in the fundamental assumptions. We're not in familiar territory here.

Re: Travel through wormholes is possible, but slow

#140

Earlier quoted context omitted.

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 s…

I'd push back against the idea of rich interiority personally, but ultimately I think that's more of a philosophical question. Practically speaking since we're engaging in this idea without the requirement to achieve continuity of consciousness, I'd argue it's potentially an unnecessary concern. If you will not continue after death, do you personally care if your replacement has interiority? On the other hand, if you want the things you care about to doing to continue getting done by a replacement, you do care that they are capable of everything you are and respond exactly as you would to every situation.

That being said I think your second challenge is more interesting. Albert Einstein's achievements are the product of both extreme knowledge/specialization, his experience and his personality. I think you'd likely have to have a "knowledge space" which can be mapped to the human "mind matrices." That does complicate things a fair bit, but in the abstract I think a "vanilla human" could plausibly be seeded with Einstein's personality and as much knowledge as you want.

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