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A Topos Perspective on State-Vector Reduction

C. J. Isham
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Abstract

A preliminary investigation is made of possible applications in quantum theory of the topos formed by the collection of all $M$-sets, where $M$ is a monoid. Earlier results on topos aspects of quantum theory can be rederived in this way. However, the formalism also suggests a new way of constructing a `neo-realist' interpretation of quantum theory in which the truth values of propositions are determined by the actions of the monoid of strings of finite projection operators. By these means, a novel topos perspective is gained on the concept of state-vector reduction.

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C. J. Isham. 2005-08-30. A Topos Perspective on State-Vector Reduction. https://doi.org/10.1007/s10773-006-9110-7

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