Unstable quasiparticles as a source of thermodynamic instabilities in the thermal nonlocal Nambu-Jona-Lasinio model
arXiv:1401.3722 · doi:10.1103/PhysRevD.89.076010
Abstract
It has already been shown that in thermal nonlocal Nambu-Jona-Lasinio models some unphysical behavior, such as a negative pressure, may arise. In this article, it is shown how this behavior can be related to the pressence of highly unstable poles of the propagator of the model, for both the Gaussian and Lorentzian regulators cases. Computations are carried out within the real time formalism, which allows to isolate the contributions from different poles and identify the source of these instabilities. It has also been shown in recent articles how these instabilities are softened by the inclusion of the Polyakov loop when a Gaussian regulator is considered. This article shows how the softening of instabilities can be understood by studying the effect of the Polyakov loop on the poles of the propagator for the Gaussian regulator.
10 pages, 12 figures, to appear at Phys. Rev. D
References in corpus (10)
- The chiral and deconfinement crossover transitions: PNJL model beyond mean field
- On covariant nonlocal chiral quark models with separable interactions
- Nonlocal chiral quark models with wavefunction renormalization: sigma properties and π-πscattering parameters
- Electrical neutrality and pion modes in the two flavor PNJL model
- Enforced neutrality and color-flavor unlocking in the three-flavor Polyakov-loop NJL model
- The Linear Sigma Model and the formation of a charged pion condensate in the presence of an external magnetic field
- Color neutrality effects in the phase diagram of the PNJL model
- Thermodynamic instabilities in dynamical quark models with complex conjugate mass poles
- Thermal Behaviour of Scattering Lengths in the Nambu--Jona-Lasinio model
- Thermal nonlocal Nambu--Jona-Lasinio model in the real time formalism