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Speakable and unspeakable after John Bell

Ian C. Percival
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Abstract

`Philosophy' was speakable for John Bell but is not for many physicists. The border between philosophy and physics is here illustrated through Brownian motion and Bell experiments. `Measurement', however, was unspeakable for Bell. His insistence that the physics of quantum measurement should not be confined to the laboratory and that physics is concerned with the big world outside leads us to examples from zoology, meteorology and cosmology.

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Ian C. Percival. 2000-12-05. Speakable and unspeakable after John Bell. https://arxiv.org/abs/quant-ph/0012021

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