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Quantum Setback For Warp Drives
KentuckyFC writes "Warp drives were generally considered impossible by mainstream scientists until 1994 when the physicist Michael Alcubierre worked out how to build a faster-than-light drive using the principles of general relativity. His thinking was that while relativity prevents faster-than-light travel relative to the fabric of spacetime, it places no restriction on the speed at which regions of spacetime may move relative to each other. So a small bubble of spacetime containing a spacecraft could travel faster than the speed of light, at least in principle. But one unanswered question was what happens to the bubble when quantum mechanics is taken into account. Now, a team of physicists have worked it out, and it's bad news: the bubble becomes unstable at superluminal speeds, making warp drives impossible (probably)."
That doesn't work. You can't transmit information faster than light; contrary to popular conception, quantum entanglement does not involve classical information transfer.
If you have one of a pair of dice, and the other is a thousand light-years away, one way to think of entanglement is to imagine that whatever number you roll is the number that shows up on the other die the next time it is rolled. Even if the two dice are linked, you can't control which number shows up, so you can't use the dice to communicate information.
entropy dictates that that everything loses to heat. This heat is at such a low energy level eventually that it can't cause any increase in energy to anything at all around it. This is how a system winds down, eventually all the energy in the atom will get sapped off this way and then it will start breaking down. Eventually devolving into the quantum soup that makes up the subatomic particles. Eventually, those too will lose energy to the space around them until everything is the same indistinguishable quantum soup.
This is the cold death scenario, and the only thing that can stop it is space itself increasing the density of energy instead of forever decreasing it. It's the expansion of space that continually provides for this loss of energy.
so no, atoms aren't perpetual motion machines. Though, for practical reasons, unless you need the machine to be functioning billions of years from now, you can call it perpetual.
Also, 0 is not "nigh impossible" - it is the definition of impossible.
Not necessarily. It may be that there are an uncountable number of possible outcomes, and each individual outcome has a zero probability, but large sets of them collectively still have positive probability. At least, models exist where this makes sense...
I am the man with no sig!
I think he said this words were _after_ his accident.
He was slowly recovering, something that seemed impossible at the beginning.
That doesn't work either because Joe doesn't know if you have rolled the dice or not.
Entangled particles are like dice that are already rolling, and they stop rolling the moment that either particle is observed.
So you and Joe each have a dice that, say, always roll the same number as each other. You look at your dice to cause it to stop rolling, and see that it rolled a 6. Joe can look at his dice too, and will also see a 6, but he doesn't know if he was the one that caused the dice to stop, or whether it was you who stopped it.
You both see a 6, but no actual information was transferred.