Time Symmetry Theory, or Retrocausality, Predicts That the Future Is Influencing the Past | Big Think

A New Quantum Theory Predicts That the Future Could Be Influencing the Past; Paul Ratner; In Big Think; 2017-07-09.

Original Sources

Matthew Leifer (Chapman University), Matt Pusey (Perimeter); Does time-symmetry in quantum theory imply retrocausality?; Foundational Questions Institute (FQXi); 2016-07-17; 28 slides.
<paywalled>Matthew S. Leifer, Matthew F. Pusey; Is a time symmetric interpretation of quantum theory possible without retrocausality?; In Proceedings of the Royal Society A; 2017-06-21; DOI:10.1098/rspa.2016.0607</paywalled>

tl;dr → Betteridge’s Law. No.


  • retrocausality
  • time symmetry
  • Perimeter Institute for Theoretical Physics in Ontario.


<quote>retrocausality does not mean that you get to send signals from the future to the past – rather that an experimenter’s measurement of a particle can influence the properties of that particle in the past, even before making their choice.</quote>


  • Matthew S. Leifer
  • Huw Price, professor, philosophy, University of Cambridge,
    …quoted for color, background & verisimilitude.


  • Einstein
  • Bell



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