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arXiv · 1611.10282

Hadamard states for quantum Abelian duality

Marco Benini·Matteo Capoferri·Claudio Dappiaggi
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Abstract

Abelian duality is realized naturally by combining differential cohomology and locally covariant quantum field theory. This leads to a C$^*$-algebra of observables, which encompasses the simultaneous discretization of both magnetic and electric fluxes. We discuss the assignment of physically well-behaved states to such algebra and the properties of the associated GNS triple. We show that the algebra of observables factorizes as a suitable tensor product of three C$^*$-algebras: the first factor encodes dynamical information, while the other two capture topological data corresponding to electric and magnetic fluxes. On the former factor we exhibit a state whose two-point correlation function has the same singular structure of a Hadamard state. Specifying suitable counterparts also on the topological factors we obtain a state for the full theory, providing ultimately a unitary implementation of Abelian duality.

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Marco Benini, Matteo Capoferri, Claudio Dappiaggi. 2016-11-30. Hadamard states for quantum Abelian duality. https://doi.org/10.1007/s00023-017-0593-y

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