Thu·Sep 8, 2005Thursday·September 8, 2005

1. 01*

   Phases of planar QCD on the torus

   Rajamani Narayanan (FIU)🇺🇸 · Herbert Neuberger (Rutgers)🇺🇸

   At infinite N, continuum Euclidean SU(N) gauge theory defined on a symmetrical four torus has a rich phase structure with phases where the finite volume system behaves as if it had infinite extent in some or all of the directions. In addition, fermions are automatically quenched, so planar QCD should be cheaper to solve numerically that full QCD. Large N is a relatively unexplored and worthwhile direction of research in lattice field theory.

   hep-latPoS(2006)·20 citations
2. 02*

   Topological charge renormalization: A test case for 3-loop vacuum calculations using overlap fermions and Symanzik improved gluons

   A. Skouroupathis🇨🇾 · H. Panagopoulos (Department of Physics, University of Cyprus, Nicosia)🇨🇾

   We calculate perturbative renormalization properties of the topological charge, using the standard lattice discretization given by a product of twisted plaquettes. We use the overlap and clover action for fermions, and the Symanzik improved gluon action for 4- and 6-link loops. We compute the multiplicative renormalization of the topological charge density to one loop; this involves only the gluon part of the action. The power divergent additive renormalization of the topological susceptibility is calculated to 3 loops.

   hep-latPoS(2006)·0 citations
3. 03*

   Hadronic light-by-light scattering contribution to the muon g-2 from lattice QCD : Methodology

   Masashi Hayakawa🇯🇵 · Thomas Blum🇺🇸 · Taku Izubuchi🇺🇸 · Norikazu Yamada🇯🇵

   The hadronic light-by-light scattering contribution to the muon g-2 is the most troublesome component of its theoretical prediction; (1) it cannot be determined from the other measurable quantities, (2) the dimensional argument and the estimation based on hadronic models imply that the magnitude of this contribution may be comparable to the discrepancy between the standard model prediction and the experimental value. The direct approach to evaluate the hadronic light-by-light scattering contribution requires the evaluation of the correlation function of {\it four} hadronic electromagnetic currents, and the summation of it over two independent four-momenta of off-shell photons, which is far from the reach of direct lattice simulation. Here we propose an alternative method using combined (QCD + QED) lattice simulations to evaluate the hadronic light-by-light scattering contribution.

   hep-lathep-phPoS(2006)·73 citations
4. 04*

   Bianchi Identities and Degeneracy of Chromomagnetic Fields in SU(2) Gluodynamics

   F.V.Gubarev🇷🇺 · S.M.Morozov (ITEP, Moscow)🇷🇺

   We investigate the non-Abelian Bianchi identities in pure SU(2) lattice Yang-Mills theory in three and four dimensions. The non-Abelian Stokes theorem proposed recently allows to formulate the Bianchi identities in terms of local physical fluxes. Then the violation of Bianchi identities becomes a well defined concept ultimately related to chromomagnetic fields degeneracy points. We present numerical evidences that in D=4 the suppression of the Bianchi identities violation destroys confinement while the removal of the degeneracy points drives the theory to the topologically non-trivial sector.

   hep-latPoS(2006)·0 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.