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Physicists provide support for retrocausal quantum theory

phys.org

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Re: Physicists provide support for retrocausal quantum theory

#4
> But by allowing for the possibility that the measurement setting for one particle can retrocausally influence the behavior of the other particle, there is no need for action-at-a-distance—only retrocausal influence.

I don't quite get it. According to GR, non-locality and retrocausality are equivalent. So how is retrocausal QM different from Bohmian mechanics/pilot wave theories?

Re: Physicists provide support for retrocausal quantum theory

#7
post #6

This would allow us to predict the future and potentially allow for time travel as well. Seems unlikely from the implications alone, but let's see what peer review of the details will tell us.

> This would allow us to predict the future and potentially allow for time travel as well.

It doesn't actually, they discuss this in the article. The laws of thermodynamics impose an arrow of time via boundary conditions, and something similar would apply here.

Re: Physicists provide support for retrocausal quantum theory

#8
post #6

This would allow us to predict the future and potentially allow for time travel as well. Seems unlikely from the implications alone, but let's see what peer review of the details will tell us.

Entanglement would too, if it allowed superluminal communication in the classical sense. But, it doesn't- you can't use entanglement to send information, even if there is a spooky interaction at a distance.

Retrocausality would probably work in the same way.

Re: Physicists provide support for retrocausal quantum theory

#9
post #7
post #6

This would allow us to predict the future and potentially allow for time travel as well. Seems unlikely from the implications alone, but let's see what peer review of the details will tell us.

> This would allow us to predict the future and potentially allow for time travel as well. It doesn't actually, they discuss this in the article. The laws of thermodynamics impose an arrow of time via boundary conditions, and something similar would apply here.

Purely as an amateur, it seems unelegant to have something that violates causality as a mechanism, but doesn't give you a way to violate cause and effect at a higher level. It's like the universe is conspiring to keep its awesome tricks from you.

Re: Physicists provide support for retrocausal quantum theory

#10
post #6

This would allow us to predict the future and potentially allow for time travel as well. Seems unlikely from the implications alone, but let's see what peer review of the details will tell us.

Unless I am missing standing, the goal is only to produce a new interpretation of quantum mechanics. That is, the predicted physics do not change, only the formulation of the theory. Therefore, anything possible under this formulation is also possible under more traditional formulation of quantum mechanics (e.g., the many world's interpretation).
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