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arXiv · 1411.1205

Comparison of different lattice definitions of the topological charge

Krzysztof Cichy·Arthur Dromard·Elena Garcia-Ramos·Konstantin Ottnad·Carsten Urbach·Marc Wagner·Urs Wenger·Falk Zimmermann
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Abstract

We present a comparison of different definitions of the topological charge on the lattice, using a small-volume ensemble with 2 flavours of dynamical twisted mass fermions. The investigated definitions are: index of the overlap Dirac operator, spectral projectors, spectral flow of the Hermitian Wilson-Dirac operator and field theoretic with different kinds of smoothing of gauge fields (HYP and APE smearings, gradient flow, cooling). We also show some results on the topological susceptibility.

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Krzysztof Cichy, Arthur Dromard, Elena Garcia-Ramos, Konstantin Ottnad, Carsten Urbach, Marc Wagner, Urs Wenger, Falk Zimmermann. 2014-11-05. Comparison of different lattice definitions of the topological charge. https://arxiv.org/abs/1411.1205

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