Dynamical overlap fermion at fixed topology

Abstract

We launched a project to perform dymanical fermion simulations using the overlap fermion formulation for sea quarks. In order to avoid the appearace of near-zero modes of the hermitian Wilson-Dirac operator $H_W$, we introduce a pair of extra Wilson fermions with a large negative mass term. Crossing of the topological boundary is then strictly prohibited, and the topological charge is conserved during simulations. It makes the simulations substantially faster compared to the algorithms which allow the topology change. We discuss on the finite volume effects due to the fixed global topology.

7 pages, 4 figures, talk presented at Lattice 2006 (chiral symmetry); to appear in Proceedings of Science, PoS(LAT2006)052

References in corpus (10)

• Dynamical overlap fermions, results with hybrid Monte-Carlo algorithm
• Lattice gauge action suppressing near-zero modes of H_W
• Localization in Lattice QCD
• Gap Domain Wall Fermions
• Evidence Against Instanton Dominance of Topological Charge Fluctuations in QCD
• Speeding up the Hybrid-Monte-Carlo algorithm for dynamical fermions
• Numerical Methods for the QCD Overlap Operator:III. Nested Iterations
• Chirality Correlation within Dirac Eigenvectors from Domain Wall Fermions
• Exact local fermionic zero modes
• Hadron spectrum, quark masses and decay constants from light overlap fermions on large lattices

Cited by in corpus (5)

• Spontaneous chiral symmetry breaking in QCD:a finite-size scaling study on the lattice
• Exploring the chiral regime with dynamical overlap fermions
• A lattice Dirac operator for QCD with light dynamical quarks
• Modifying the molecular dynamics action to increase topological tunnelling rate for dynamical overlap fermions
• Theta vacuum physics from QCD at fixed topology