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Can nonlocal Dirac operators be topologically proper ?

Ting-Wai Chiu
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Abstract

By examining the analyticity of a sequence of topologically-proper lattice Dirac operators, we show that they tend to a nonlocal Dirac operator. This implies that a nonlocal lattice Dirac operator can have exact zero modes satisfying the Atiyah-Singer index theorem, in gauge backgrounds with nonzero topological charge.

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Ting-Wai Chiu. 2000-11-15. Can nonlocal Dirac operators be topologically proper ?. https://doi.org/10.1016/s0370-2693(00)01365-4

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