Thursday, 14 March 2019

Physicists "reverse time" using quantum computer

quote [ Researchers from the Russia teamed up with colleagues from the US and Switzerland and returned the state of a quantum computer a fraction of a second into the past. They also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. ]

No, they didn't turn back time like Cher wishes she could, but it's still pretty neat what they did.

Here's an explanation I found:

This reversal was not performed in a closed system, but was instead driven by a specific device. The second law of thermodynamics still holds in general for closed systems. The flow of time was not ever actually reversed in this system, however a quantum states evolution was successfully reversed. Its cool and useful, but it's not time travel.
[SFW] [science & technology] [+3 Interesting]
[by JWWargo@12:15amGMT]

Comments

damnit said @ 3:23am GMT on 14th Mar
So there's still a chance for reversing entropy?
cb361 said @ 2:08pm GMT on 16th Mar [Score:1 Underrated]
Shut up! Shut up! You’re just making more of it!
ubie said[1] @ 3:05pm GMT on 14th Mar
Like most of these kinds of articles I'm going to take a 'wait and see' approach.
Nifty and all if true, but I have strong counts pending peer review and independent replication of the experiment.
Hell, with these kinds of articles i often doubt what is written is what the paper or scientists actually say.
snowfox said[1] @ 6:31pm GMT on 14th Mar
Is that really returning to the past? This seems more like they found the probability of an electron making two changes that negate eachother, returning the electron to its original position and state, then they set up another experiment to find the probability of electrons happening to take up states that we would think of as a reversal through our own human error in understanding. It isn't that these electrons are going from chaos to order (if there is such a thing), but whether they might all happen to come together... and they do that frequently or else atoms would not be possible. Chaos, which is probably a word for probability, results in things we'd perceive as order on the regular; it is a system that produces order.

All this comparison to the billiard balls is a nuisance because we know that sub-atomic does not scale to Newtonian. It's not a good analogy.

My money is still on neutrinos. I don't think they appear and disappear, not really. Particle-wave duality dictates that all particles are waves. So if we're seeing a pattern of presence and absence in a wave, that would suggest a pattern of inconsistent constructive interference, which is why neutrinos sometimes appear to be there and sometimes not. These oscillating waves sometimes interact in a way that makes a particle, and sometimes don't. The neutrinos' fundamental wave components are there, but not always constructively interfering. Combine this with the implications of the double slit experiment, and you get this notion that what is "real" versus what is merely possible but has not happened is a matter of whether the probability is high enough that it creates a dense, perceptible band. The ideas of a strong frequency and high probability are fundamentally the same.

In other words, it's all just a good vibration, baby.

Any physicists on here care to tell me what I'm missing about this experiment that causes it to have profound implications?
Ned Ryerson said @ 7:42pm GMT on 14th Mar
Bing again! You are sharp as a tack today! Do you have life insurance, Phil? Because if you do, you could always use more. Right! I mean, who couldn't? But you want to know something? I gots a feeling... you ain't got any. Am I right or am I right or am I right? Am I right? Right? Right?
ethanos said @ 9:41pm GMT on 14th Mar
when i get my time machine, i'm going to fritter away all my extra time.
mechanical contrivance said @ 1:19pm GMT on 15th Mar

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