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Classification of Subsystems for Local Nets with Trivial Superselection Structure

Sebastiano Carpi·Roberto Conti
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Abstract

Let F be a local net of von Neumann algebras in four spacetime dimensions satisfying certain natural structural assumptions. We prove that if F has trivial superselection structure then every covariant, Haag-dual subsystem B is the fixed point net under a compact group action on one component in a suitable tensor product decomposition of F. Then we discuss some application of our result, including free field models and certain theories with at most countably many sectors.

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Sebastiano Carpi, Roberto Conti. 2000-02-24. Classification of Subsystems for Local Nets with Trivial Superselection Structure. https://doi.org/10.1007/pl00005550

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