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Quantum Computer Time Travel

The post's headline:
'Physicists Reverse Time using Quantum Computer'

My comment:

Despite the headline this is not reversing time.
This is very funny though I suppose the authors disagree.
From the post:
The team set out to calculate the probability to observe an electron "smeared out" over a fraction of a second spontaneously localizing into its recent past. It turned out that even if one spent the entire lifetime of the universe — 13.7 billion years — observing 10 billion freshly localized electrons every second, the reverse evolution of the particle's state would only happen once. And even then, the electron would travel no more than a mere one ten-billionth of a second into the past.

The really, really funny aspect is they (and their sophisticated software; this was not done with a real particle) could have calculated any amount of time from that ridicuous time specified all the way to near infinity.
This smearing of time arises from being unable to measure precisely the time and location of an event, when it is localized.
At the moment of observation the particle might have arrived one ten-billionth of a second before the observation.

This timing for its detection does not mean the particle went back in time by that tiny increment compared to now.
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