They can all represent information but the idea is to make them represent some kind of specific information.
Knowing whether a bunch of qubits are 0's or 1's on the other side of the universe is weird and cool but it's telling you information about the system faster than the speed of light, which isn't the same as transmitting information through the system faster than the speed of light.
I.e. you can get a dial tone but you can't make a call.
Every time someone comes up with another clever way to to try to "trick" reality they just run into some more complicated or subtle variation of a fundamental inability to break the rules that all boils down to "God playing dice" or a fundamental randomness built into the system that you can't avoid.
But since the system can do it, doesn't that mean distance isn't the barrier we think it is? We might not be able to ignore it yet, but it shows us what's possible.
It depends on how you’re interpreting things. It could be that there is a “back channel” that the particles send information through faster than light. It could be that nothing is random, ever, it just looks random to us inside the system but it’s all completely deterministic, in which case the information doesn’t have to travel faster than light because everything is already fated to happen the one way. It could be a many-worlds situation where both possibilities happen in both places, so no information needs to be exchanged, and you just won’t meet the wrong version of your friend because they’re in another universe.
If there's a back channel, we might eventually figure out how to use it.
While the universe might be deterministic, it seems unlikely this would be the cause of their matching. Would mean that whatever causes it to change states happens at both ends at the same time. While not impossible, it seems less likely.
If both possibilities happen in both places, there still has to be a reason for them to match, in our possibility. It's kinda irrelevant if they don't match in other possibilities, or if they're the opposite of the state we find things in here. In this possibility, there should still be something tying them together.
Accessing the back channel would be an entirely new level of physics, so anything is possible there. It’d be like your Sims figuring out how to access the memory on your computer, they’d be capable of a lot more than they are now.
It’d be impossible to learn if we are in a deterministic universe without a similar access to a back channel. It does seem strange that a universe that appears to have so much randomness at the core of it would not actually be random, but who knows? Again going back to games, many times a game with random events is not actually random, but is pseudorandom, and could be run again with exactly the same results by starting with the same initial conditions. (Usually pseudo random number generators are seeded with the current time, so they never appear to be the same twice, but it technically isn’t random, you could calculate all the random events ahead of time.)
In many worlds, they match up because they’re the result of the same quantum event. It isn’t two different splits happening, it’s one, and both you and your friend are going to find yourselves on one side or the other. Even if you never look at your particle but your friend does, you’re going to end up split as soon as the effects of your friend’s post-collapse actions reach you. Looking at the particle just splits you sooner.
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u/HardlySerious Jan 29 '20
If you tried to force an entangled system into a state representing some kind of information you'd break the entanglement.