Paper: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.13... > We construct a metrology experiment in which the metrologist can sometimes amend the input state by simulating a closed timelike curve, a worldline that travels backward in time. The existence of closed timelike curves is hypothetical. Nevertheless, they can be simulated probabilistically by quantum-teleportation circuits. We leverage such simul…
"Our Gedankenexperiment demonstrates that..." "Gedankenexperiment" sounds an awful lot like "thought experiment".
Scientists simulate backward time travel using quantum entanglement
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Re: Scientists simulate backward time travel using quantum entanglement
#22Re: Scientists simulate backward time travel using quantum entanglement
#23Layperson's read but the paper seems to say "this is weird we were accurate than should be possible" combined with "causal order wouldn't make sense here" Much less "we found time travel" and more "that was weird maybe it was time travel". Also note that to my knowledge there is no form of talking about entanglement that involves time before entanglement or any meaningful manipulation of the entangled particle. Thus…
> unlikely to make a meaningful difference at distances measured less than how far light travels in that time PBS Space Time did an episode that posed the question as a delayed choice quantum eraser experiment where the “long” leg is farther away, like on the moon, and we somehow reflect a particle back and forth to delay the observation indefinitely. I also wonder if they can do something like this at CERN. Their co…
Re: Scientists simulate backward time travel using quantum entanglement
#24Layperson's read but the paper seems to say "this is weird we were accurate than should be possible" combined with "causal order wouldn't make sense here" Much less "we found time travel" and more "that was weird maybe it was time travel". Also note that to my knowledge there is no form of talking about entanglement that involves time before entanglement or any meaningful manipulation of the entangled particle. Thus…
> unlikely to make a meaningful difference at distances measured less than how far light travels in that time PBS Space Time did an episode that posed the question as a delayed choice quantum eraser experiment where the “long” leg is farther away, like on the moon, and we somehow reflect a particle back and forth to delay the observation indefinitely. I also wonder if they can do something like this at CERN. Their co…
The more plausible explanation behind the delayed choice quantum eraser involves Heisenberg's Uncertainty Principle, which states that you cannot obtain position and momentum to a high degree of accuracy at the same time. Einstein's EPR paradox "proved" quantum physics incorrect by setting the Uncertainty Principle against Entanglement. He did this by a thought experiment that entangled two particles, and measuring the position of one and the momentum of the other to thwart the Uncertainty Principle.
The delayed quantum choice eraser is a realization of Einstein's thought experiment. However, what Einstein didn't realize was that while the standard double slit experiment produces a pattern at the screen that gives you the momentum information, entangling two particles creates a different pattern at the screen that causes the particles by themselves to give neither momentum nor position information. The delayed quantum choice eraser initially recovers the position information by combining information from both particles, but by choosing the other set of detectors you can "give up" that information to gain the momentum information. Either way, you are still unable to obtain both pieces of information at the same time.
Source: I am writing a book on Quantum Physics and have spent months doing research and finding out that even many quantum physics Youtubers routinely say misinformation. By far the worst is the incorrect idea that a which-way detector on the double slit experiment will produce two bands as if the particles are marble-like. It doesn't, it destroys the interference pattern, producing a single slit pattern. This sounds like a minor detail, but it contains the realization that quantum physics particles ALWAYS act like waves, even after a measurement, and wave-particle duality is a misnomer.
Re: Scientists simulate backward time travel using quantum entanglement
#25Paper: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.13... > We construct a metrology experiment in which the metrologist can sometimes amend the input state by simulating a closed timelike curve, a worldline that travels backward in time. The existence of closed timelike curves is hypothetical. Nevertheless, they can be simulated probabilistically by quantum-teleportation circuits. We leverage such simul…
"Our Gedankenexperiment demonstrates that..." "Gedankenexperiment" sounds an awful lot like "thought experiment".
Re: Scientists simulate backward time travel using quantum entanglement
#26Re: Scientists simulate backward time travel using quantum entanglement
#27Earlier quoted context omitted.
> unlikely to make a meaningful difference at distances measured less than how far light travels in that time PBS Space Time did an episode that posed the question as a delayed choice quantum eraser experiment where the “long” leg is farther away, like on the moon, and we somehow reflect a particle back and forth to delay the observation indefinitely. I also wonder if they can do something like this at CERN. Their co…
I'm reading (well listening to) a sci-fi novel based on that premise called "Quantum Radio". Pretty classic techno-thriller, complete with shadowy organizations. I really enjoyed the premise and setup of CERN data being used as a quantum radio reading messages from the future, or perhaps parallel universes.
Beware, it's a review so there are possible spoilers.
Re: Scientists simulate backward time travel using quantum entanglement
#28Wow these ads are intrusive. I just got done listening to Penrose talking about this. Interesting timing.
Re: Scientists simulate backward time travel using quantum entanglement
#29Earlier quoted context omitted.
"Our Gedankenexperiment demonstrates that..." "Gedankenexperiment" sounds an awful lot like "thought experiment".
That’s literally what it means, and it’s a minor nitpick I have - it’s an English paper, just use English. Using the German word here just increases noise.
So what the authors are saying is "We're basically doing a similar thing as Einstein did". Jargon is to be avoided but this is more like a tribute to the great physicist Einstein.
Re: Scientists simulate backward time travel using quantum entanglement
#30What do we want? Time-Travel! When do we want it? Doesn't matter!