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arXiv · hep-lat/9810002

Topological Phases in Neuberger-Dirac operator

Ting-Wai Chiu
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Abstract

The response of the Neuberger-Dirac fermion operator $D=\Id + V$ in the topologically nontrivial background gauge field depends on the negative mass parameter $m_0$ in the Wilson-Dirac fermion operator $D_w$ which enters $D$ through the unitary operator $V = D_w (D_w^{\dagger} D_w)^{-1/2}$. We classify the topological phases of $D$ by comparing its index to the topological charge of the smooth background gauge field. An exact discrete symmetry in the topological phase diagram is proved for any gauge configurations. A formula for the index of D in each topological phase is derived by obtaining the total chiral charge of the zero modes in the exact solution of the free fermion propagator.

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BibTeXRIS

Ting-Wai Chiu. 1999-07-16. Topological Phases in Neuberger-Dirac operator. https://doi.org/10.1103/physrevd.60.114510

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