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arXiv · 1912.12819

Deformation quantization and homological reduction of a lattice gauge model

Markus J. Pflaum·Gerd Rudolph·Matthias Schmidt
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Abstract

For a compact Lie group $G$ we consider a lattice gauge model given by the $G$-Hamiltonian system which consists of the cotangent bundle of a power of $G$ with its canonical symplectic structure and standard moment map. We explicitly construct a Fedosov quantization of the underlying symplectic manifold using the Levi-Civita connection of the Killing metric on $G$. We then explain and refine quantized homological reduction for the construction of a star product on the symplectically reduced space in the singular case. Afterwards we show that for $G = \operatorname{SU} (2)$ the main hypotheses ensuring the method of quantized homological reduction to be applicable hold in the case of our lattice gauge model. For that case, this implies that the - in general singular - symplectically reduced phase space of the corresponding lattice gauge model carries a star product.

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Markus J. Pflaum, Gerd Rudolph, Matthias Schmidt. 2019-12-30. Deformation quantization and homological reduction of a lattice gauge model. https://arxiv.org/abs/1912.12819

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