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>The laws of physics as we know them today don't forbid time travel. In fact, they propose a fairly specific means of doing it via accelerating one side of a tr
by nobody9999 5y ago
>The laws of physics as we know them today don't forbid time travel. In fact, they propose a fairly specific means of doing it via accelerating one side of a traversable wormhole to near the speed of light.
That applies to time travel into the past.
It's obvious, but it bears noting that the converse is a lot simpler. I say that because, IIUC (and that's a real question), quantum mechanics treats the time dimension as symmetrical, which contradicts observation, at least to this point.
Is that because QM is wrong on that point? Which seems unlikely, since it's one of the most precisely confirmed (by observation) theories we have.
Or is there something about the "macro" world that destroys that symmetry?
I don't have the answer, but it's clear that in a particular reference frame, we move forward in time at a rate of 1 sec/second.
Again, that's obvious, but based on my (limited) understanding, that seems to contradict QM.
- caf 5y agoI say that because, IIUC (and that's a real question), quantum mechanics treats the time dimension as symmetrical, which contradicts observation, at least to this point. As far as I'm aware, the weak force is known (and experimentally demonstrated) to break time-reversal symmetry. It's only combined Charge-Parity-Time symmetry that QM maintains. (This still does not explain how a macro arrow of time arises, though)
- GoblinSlayer 5y agoThere's no contradiction there. Time symmetry is a mathematical property, so time reversal exists only in mathematics, this is perfectly expected behavior.