Low-lying spectrum for lattice Dirac operators with twisted mass

Christof Gattringer; Stefan Solbrig

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arXiv · hep-lat/0509079

Low-lying spectrum for lattice Dirac operators with twisted mass

Christof Gattringer·Stefan Solbrig

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Abstract

We analyze the low-lying spectrum and eigenmodes of lattice Dirac operators with a twisted mass term. The twist term expels the eigenvalues from a strip in the complex plane and all eigenmodes obtain a non-vanishing matrix element with gamma-5. For a twisted Ginsparg-Wilson operator the spectrum is located on two arcs in the complex plane. Modes due to non-trivial topological charge of the underlying gauge field have their eigenvalues at the edges of these arcs and obey a remnant index theorem. For configurations in the confined phase we find that the twist mainly affects the zero modes, while the bulk of the spectrum is essentially unchanged.

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Christof Gattringer, Stefan Solbrig. 2005-09-22. Low-lying spectrum for lattice Dirac operators with twisted mass. https://arxiv.org/abs/hep-lat/0509079

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