On the logical structure of Bell theorems.

ORAL

Abstract

Some specific predictions of quantum mechanics are inconsistent with local realism, a phenomenon known as nonlocality. Despite overwhelming evidence for quantum mechanics, the practical difficulties of detector efficiency and coordinating space-like separated measurements have provided loopholes for a classical worldview. New experiments have been proposed to meet these challenges, based around a new kind of nonlocality proof called an ``EPR Bell inequality''. Much investment is now being made to realize these proofs experimentally. We show all these proposals are fundamentally flawed. We focus on a series of designs that have appeared in \textit{PRL} and \textit{PRA} for loophole-free Bell experiments. These experiments use hyperentangled two-photon quantum states to generate experimental data supposedly at odds with local realism. We show how to produce identical results using a single coin, and explain where the logical flaw can be found. To understand our nonclassical world, we must understand precisely the experimental evidence for nonlocality. This tempting shortcut is a logical, theoretical and experimental dead end. http://www.arxiv.org/abs/quant-ph/0512201.

Authors

  • Jonathan Walgate

    Perimeter Institute, Waterloo, Canada, Perimeter Institute for Theoretical Physics

  • Anne Broadbent

    Universite de Montreal

  • Hilary Carteret

    University of Calgary

  • Andre Methot

    Universite de Montreal