Speaker
Bruno Mintz
(Universidade do Estado do Rio de Janeiro - Brazil)
Description
In an attempt to solve the problem of spurious gauge copies in the path integral approach to gauge theories, V. N. Gribov proposed in 1978 a method to restrict the integration domain of the path integral to only one gauge field representative of each physical field configuration. As a result, the quadratic part of the gluon propagator is modified in the infrared, so that it acquires complex poles, i.e., complex "masses". This implies the absence of gluons in the physical spectrum, which is a necessary condition for confinement. An analogous reasoning
may be applied to quark fields coupled to the gauge fields. As a consequence, the quark propagator also gets modified in the infrared, giving rise to unphysical propagators (i.e., with complex poles) at small momenta. Such a property is understood as a sign of both quark confinement and of the breaking of chiral symmetry in the vacuum. In this work, we study the thermodynamics of this model by exactly calculating the partition function using standard methods of finite-temperature quantum field theory. We find that the infrared behavior of the
quark propagator leads to a highly nontrivial pressure as a function of the temperature, which is qualitatively close to the results from lattice QCD at finite temperature.
Author
Bruno Mintz
(Universidade do Estado do Rio de Janeiro - Brazil)
Co-author
Marcelo Guimaraes
(Universidade do Estado do Rio de Janeiro - Brazil)
