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The Landau gauge gluon and ghost propagators in 4D SU(3) gluodynamics in large lattice volumes

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 نشر من قبل Igor Bogolubsky
 تاريخ النشر 2008
  مجال البحث
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 تأليف I.L. Bogolubsky




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We present recent results of the Landau gauge gluon and ghost propagators in SU(3) pure gauge theory at Wilson beta=5.7 for lattice sizes up to 80^4 corresponding to physical volumes up to (13.2 fm)^4. In particular, we focus on finite-volume and Gribov copy effects. We employ a gauge fixing method that combines a simulated annealing algorithm with finalizing overrelaxation. We find the gluon propagator for the largest volumes and at q^2 ~ 0.01 GeV^2 to become flat. Although not excluded by our data, there is still no clear indication of a gluon propagator tending towards zero in the zero-momentum limit. New data for the ghost propagator are reported, too.



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