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arXiv · 1402.6976

Spectral theorem in noncommutative field theories: Jacobi dynamics

Antoine Géré·Jean-Christophe Wallet
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Abstract

Jacobi operators appear as kinetic operators of several classes of noncommutative field theories (NCFT) considered recently. This paper deals with the case of bounded Jacobi operators. A set of tools mainly issued from operator and spectral theory is given in a way applicable to the study of NCFT. As an illustration, this is applied to a gauge-fixed version of the induced gauge theory on the Moyal plane expanded around a symmetric vacuum. The characterization of the spectrum of the kinetic operator is given, showing a behavior somewhat similar to a massless theory. An attempt to characterize the noncommutative geometry related to the gauge fixed action is presented. Using a Dirac operator obtained from the kinetic operator, it is shown that one can construct an even, regular, weakly real spectral triple. This spectral triple does not define a noncommutative metric space for the Connes spectral distance.

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Antoine Géré, Jean-Christophe Wallet. 2014-02-27. Spectral theorem in noncommutative field theories: Jacobi dynamics. https://doi.org/10.1088/1742-6596/634/1/012006

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