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Title: Topological Gauge Actions on the Lattice as Overlap Fermion Determinants
Overlap fermion on the lattice has been shown to properly reproduce topological aspects of gauge fields. In this paper, we review the derivation of Overlap fermion formalism in a torus of three space-time dimensions. Using the formalism, we show how to use the Overlap fermion determinants in the massless and infinite mass limits to construct different continuum topological gauge actions, such as the level-k Chern–Simons action, “half-CS” term and the mixed Chern–Simons (BF) coupling, in a gauge-invariant lattice UV regulated manner. Taking special Abelian and non-Abelian background fields, we demonstrate numerically how the lattice formalism beautifully reproduces the continuum expectations, such as the flow of action under large gauge transformations.
Authors:
;
Award ID(s):
1913010
Publication Date:
NSF-PAR ID:
10334760
Journal Name:
Universe
Volume:
8
Issue:
6
Page Range or eLocation-ID:
332
ISSN:
2218-1997
Sponsoring Org:
National Science Foundation
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