Approximation Theory for Matrices
نویسنده
چکیده
There are many situations in which it is desirable to evaluate a function of a matrix. For instance, in lattice quantum field theory it is sometimes desirable to evaluate the square root of a discretised Dirac operator D/ in order to calculate the effects of varying the number of fermionic flavours [1,2,3,4,5], or to construct a good approximation to Neuberger’s operator for GinspargWilson fermions by evaluating the sign function [6,7,8,9].
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