Deflation of Eigenvalues for GMRES in Lattice QCD
نویسندگان
چکیده
This paper looks at the iterative solution of complex, non-Hermitian systems of linear equations associated with a lattice QCD problem in particle physics. Let the n by n system of equations be Ax = b. We use a version of the GMRES method that deflates eigenvalues and can solve systems with multiple right-hand sides. We give examples that show deflating eigenvalues can make a significant improvement in the convergence for QCD matrices. We work with the non-Hermitian Wilson-Dirac matrix M(x, y) given by,
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