Originally posted by Obbe
If AI has been perfected and tamed, humanity would use AI to unify quantum mechanics with general relativity under a Theory of Everything. If we know how everything works, like quantum entanglement, and if teleportation of information has been mastered, why wouldn't we be able to teleport matter?
There are a couple of different trains of thought that need to be detangled here. Teleportation et al and FTL are sometimes related but different things.
Subluminal (slower than light) quantum teleportation of information is possible because a specific kind of correlation exists in certain properties between entangled parts of a QM system.
2 channels are used in quantum teleportation, a quantum channel and a classical channel.
The quantum channel is used to generate these correlated values for certain measured properties between the 2 ends. This part happens FTL. By itself this data is random on either end so it useless, looks like noise
Then the classic channel is used to send a "key" that turns the random quantum data into structured classical information
Structured information cannot be transmitted FTL using quantum entanglement.
https://en.wikipedia.org/wiki/No-communication_theoremAs for why we can't teleport matter, matter actually does teleport on quantum scales. A particle can even quantum tunnel through an otherwise impassible barrier and even do it FTL!
Unfortunately you can't take advantage of this at the scale of any macroscopic, classical structure: where and how this happens is also totally random. So on a macroscopic scale, even if you were to somehow induce all the particles in your body to enter a state of superposition in a way where they can quantum tunnel, they would do so at random. Some of your particles will never make the leap outside the barrier. And those that do will be scattered in space and time.
The general point can be taken as: the rules of reality are whatever they are, we only get to find out what they are and what to do about it.
There's no guarantee that a trillion years of scientific or technological advancement by a powerful AI will create FTL travel because it's possible that's just a hard limit of the rules of reality.
At a certain point we have to step back from all of our ideas about "possible and impossible" and acknowledge that there are actually genuine facts about the reality we all seem to inhabit. Facts that we cannot just perseverance-and-ingenuity our way around.
After all isn't matter also information? If humans in the future with the aid of perfect AI have figured out how to manipulate matter/teleportation, we would no longer need to poop. We could teleport the waste right out of our bodies. We wouldn't have to eat either, you could teleport all the correct nutrition right into a body. We wouldn't have to age either, our bodies could be maintained at whatever state we wish.
On a philosophical level completely seriously, it depends on what your definition of "is" is.
Matter is defined by certain informational properties. In a sense you can say it IS information because the information is the totality of everything we could ever find out about it even in principle. You might compare this loosely to whether the noumenal and the phenomenal are the exact same thing, or if one of those is defined by a particular kind of statement you can make about the other.
On a practical level, entanglement is a correlation in stochastic outcomes of measurements of entangled parts of a system.
So the principles of the reasoning by which it's instantaneous in the first place is also why you can't "control" the outcome: it's stochastic/random.
So for example you might be able to entangle the position property of the molecules in your body to something else by putting your body into a state of superposition. But you can't control what that superposition ultimately produces as the new vakue for the position property. It's just random i.e. you die.
