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The jump process introduced by J. S. Bell in 1986, for defining a quantum field theory without observers, presupposes that space is discrete whereas time is continuous. In this letter, our interest is to find an analogous process in discrete time. We argue that a genuine analog does not exist, but provide examples of processes in discrete time that could be used as a replacement.


This is a pre-copy-editing, author-produced PDF of an article accepted for publication in EPL, volume 72, in 2005 following peer review. The definitive publisher-authenticated version is available online at DOI: 10.1209/epl/i2005-10297-5.

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European Physical Society



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