Retrocausality: Physicists Ponder Whether the Future Can Influence the Past

Communication Price Entanglement Mechanics

Issue 9 of the wonderful online magazine Nautilus is now available to read, and offers a fantastic collection of articles on the theme of 'Time'. One of the pieces I recommend checking out is George Musser's article "The Quantum Mechanics of Fate", which delves into the (possible) mystery of retrocausality in modern physics:

Physicists as renowned as John Wheeler, Richard Feynman, Dennis Sciama, and Yakir Aharonov have speculated that causality is a two-headed arrow and the future might influence the past. Today, the leading advocate of this position is Huw Price, a University of Cambridge philosopher who specializes in the physics of time. “The answer to the question, ‘Could the world be such that we do have a limited amount of control over the past,’ ” Price says, “is yes.” What’s more, Price and others argue that the evidence for such control has been staring at us for more than half a century.

That evidence, they say, is something called entanglement, a signature feature of quantum mechanics...

...The standard interpretation of entanglement is that there is some kind of instant communication happening between the two particles. Any communication between them would have to travel the intervening distance instantaneously—that is, infinitely fast. That is plainly faster than light, a speed of communication prohibited by the theory of relativity.

.. ( via ).

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