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arXiv · 0904.1353

Finite size phase transitions in QCD with adjoint fermions

Guido Cossu·Massimo D'Elia
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Abstract

We perform a lattice investigation of QCD with three colors and 2 flavors of Dirac (staggered) fermions in the adjoint representation, defined on a 4d space with one spatial dimension compactified, and study the phase structure of the theory as a function of the size Lc of the compactified dimension. We show that four different phases take place, corresponding to different realizations of center symmetry: two center symmetric phases, for large or small values of Lc, separated by two phases in which center symmetry is broken in two different ways; the dependence of these results on the quark mass is discussed. We study also chiral properties and how they are affected by the different realizations of center symmetry; chiral symmetry, in particular, stays spontaneously broken at the phase transitions and may be restored at much lower values of the compactification radius. Our results could be relevant to a recently proposed conjecture of volume indepedence of QCD with adjoint fermions in the large Nc limit.

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Guido Cossu, Massimo D'Elia. 2009-05-25. Finite size phase transitions in QCD with adjoint fermions. https://doi.org/10.1088/1126-6708/2009/07/048

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