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Polynomial Filtered HMC -- an algorithm for lattice QCD with dynamical quarks

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 نشر من قبل Waseem Kamleh
 تاريخ النشر 2011
  مجال البحث
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Polynomial approximations to the inverse of the fermion matrix are used to filter the dynamics of the upper energy scales in HMC simulations. The use of a multiple time-scale integration scheme allows the filtered pseudofermions to be evolved using a coarse step size. We introduce a novel generalisation of the nested leapfrog which allows for far greater flexibility in the choice of time scales. We observe a reduction in the computational expense of the molecular dynamics integration of between 3--5 which improves as the quark mass decreases.



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