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arXiv · 0909.5252

Construction of a topological charge on fuzzy S^2 x S^2 via Ginsparg-Wilson relation

Hajime Aoki·Yoshiko Hirayama·Satoshi Iso
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Abstract

We construct a topological charge of gauge field configurations on a fuzzy S^2xS^2 by using a Dirac operator satisfying the Ginsparg-Wilson relation. The topological charge defined on the fuzzy S^2xS^2 can be interpreted as a noncommutative (or matrix) generalization of the 2nd Chern character on S^2xS^2. We further calculate the number of chiral zero modes of the Dirac operator in topologically nontrivial gauge configurations. Generalizations of our formulation to fuzzy (S^2)^k are also discussed.

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Hajime Aoki, Yoshiko Hirayama, Satoshi Iso. 2009-12-30. Construction of a topological charge on fuzzy S^2 x S^2 via Ginsparg-Wilson relation. https://doi.org/10.1103/physrevd.80.125006

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