Bell and Non-Locality

  • C. K. Raju
Part of the Fundamental Theories of Physics book series (FTPH, volume 65)


Does time have a non-trivial local structure? This question is new to physics, but central to the rest of this exposition. We explain how the notion of a structured time may be formulated. If time in reality is structured then physics cannot be based on differential equations alone, but needs to be founded on a new logic. The relation of such a new logic to quantum logic is postponed till Chapter VIB, while questions about the global structure of time are postponed till Chapter VII.

The previous chapter concluded by recommending the hypothesis of a tilt in the arrow of time. This hypothesis has two consequences: a structured time and non-locality. We outline the first consequence and indicate how most recognized new features about time in q.m. fit into the perspective of a (microphysically) structured time, whereas hidden variable theories deny the existence of this structure by supposing that ‘reality’ cannot but be definite. The rest of this chapter examines the physical acceptability of non-locality in the context of Bell’s inequalities.

We develop the background and state the inequalities. We point out the difficulty with inefficient detectors and try to correct the popular misconception that the inequalities have been conclusively violated in experiments. Without rejecting q.m., and without accepting hidden variables, we argue that the intuitive notion of locality is fuzzy and unreliable, while difficulties in the mathematical formulation of the notion of locality make ‘non-locality’ merely a disreputable tag. Finally, we point out that nothing in classical physics justifies the polemic of spookiness applied to non-locality — for several centuries, locality has remained a desirable metaphysical requirement, rarely satisfied by physical theory.


Classical Physic Structure Time Intuitive Notion Tense Logic Spacelike Separation 
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Notes and References

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Copyright information

© Springer Science+Business Media Dordrecht 1994

Authors and Affiliations

  • C. K. Raju
    • 1
    • 2
  1. 1.Indian Institute of Advanced StudyRashtrapati NivasShimlaIndia
  2. 2.Centre for Development of Advanced ComputingNew DelhiIndia

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