
Physicists reverse time using quantum computer - lelf
https://phys.org/news/2019-03-physicists-reverse-quantum.html
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sctb
Most comments moved to
[https://news.ycombinator.com/item?id=19378567](https://news.ycombinator.com/item?id=19378567).

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hownottowrite
Actual Study: "Arrow of Time and its Reversal on IBM Quantum Computer"
[https://arxiv.org/pdf/1712.10057.pdf](https://arxiv.org/pdf/1712.10057.pdf)

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turc1656
This is a garbage article. They are basically taking the concept of entropy
and saying that because they found a way to force something to happen that is
insanely improbable it's "reversing time". That's nonsense.

That's like saying that hydrogen and oxygen atoms bonded to form water
molecules and using electrolysis to split them back into hydrogen and oxygen
is time travel. It's completely absurd.

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biscuitb0b
No, it's actually quite different. What you're suggesting is that they
manually scattered each electron, and then brought each one manually back into
place. What actually occurred is that a completely different state was
induced, which effectively 'reversed time' (I really hate that phrase). I
found a pdf of the study, but I lost it among all the 'Have scientists created
a TARDIS?'s. Basically, it said the maths, and the probability of an electron
spontaneously entering the state. You could probably find it, if you really
wanted to.

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codeulike
tihs yloh

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johnminter
Quantum Leap, here we come (grin)

