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arXiv · hep-lat/9812003

Axial anomaly and topological charge in lattice gauge theory with Overlap Dirac operator

David H. Adams
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Abstract

An explicit, detailed evaluation of the classical continuum limit of the axial anomaly/index density of the overlap Dirac operator is carried out in the infinite volume setting, and in a certain finite volume setting where the continuum limit involves an infinite volume limit. Our approach is based on a novel power series expansion of the overlap Dirac operator. The correct continuum expression is reproduced when the parameter $m_0$ is in the physical region $0<m_0<2$. This is established for a broad range of continuum gauge fields. An analogous result for the fermionic topological charge, given by the index of the overlap Dirac operator, is then established for a class of topologically non-trivial fields in the aforementioned finite volume setting. Problematic issues concerning the index in the infinite volume setting are also discussed.

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BibTeXRIS

David H. Adams. 2001-10-04. Axial anomaly and topological charge in lattice gauge theory with Overlap Dirac operator. https://doi.org/10.1006/aphy.2001.6209

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