Comparing lattice Dirac operators in smooth instanton backgrounds
نویسنده
چکیده
We compare the behavior of different lattice Dirac operators in gauge backgrounds which are lattice discretizations of a classical instanton. In particular we analyze the overlap Dirac operator, a chirally improved Dirac operator and the standard Wilson operator. We discuss the flow of real eigenvalues as a function of the instanton size. An analysis of the eigenvectors shows that, due to their extended nature, overlap fermions have problems with reproducing the continuum zero mode for moderately small instantons. PACS: 11.15.Ha
منابع مشابه
ar X iv : h ep - l at / 0 11 00 15 v 1 5 O ct 2 00 1 1 Chirally improved Dirac operators : Studying the sensitivity to topological excitations for zero and finite temperature ∗
We discuss the construction and properties of an approximate solution of the Ginsparg-Wilson equation, the so-called chirally improved lattice Dirac operator. In particular we study the behavior of its eigenmodes in smooth instanton backgrounds as well as for thermalized gauge configurations on both sides of the QCD phase transition. We compare with results from other Dirac operators including ...
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تاریخ انتشار 2001