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arXiv · 1606.01129

On equivariant Chern-Weil forms and determinant lines

Daniel S. Freed
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Abstract

A strong from of invariance under a group G is manifested in a family over the classifying space BG. We advocate a differential-geometric avatar of BG when G is a Lie group. Applied to G-equivariant connections on smooth principal or vector bundles, the equivariance-->families principle converts the G-equivariant extensions of curvature and Chern-Weil forms to the standard nonequivariant versions. An application of this technique yields the moment map of the determinant line of a G-equivariant Dirac operator, which in turn sheds light on some anomaly formulas in quantum field theory.

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Daniel S. Freed. 2016-06-03. On equivariant Chern-Weil forms and determinant lines. https://arxiv.org/abs/1606.01129

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