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arXiv · hep-lat/9905003

A lattice implementation of the eta-invariant and effective action for chiral fermions on the lattice

Tatsumi Aoyama·Yoshio Kikukawa
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Abstract

We consider a lattice implementation of the eta-invariant, using the complex phase of the determinant of the simplified domain-wall fermion, which couples to an interpolating five-dimensional gauge field. We clarify the relation to the effective action for chiral Ginsparg-Wilson fermions. The integrability, which holds true for anomaly-free theories in the classical continuum limit, is not assured on the lattice with a finite spacing. A lattice expression for the five-dimensional Chern-Simons term is obtained.

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Tatsumi Aoyama, Yoshio Kikukawa. 2000-06-07. A lattice implementation of the eta-invariant and effective action for chiral fermions on the lattice. https://arxiv.org/abs/hep-lat/9905003

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