Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential The effective...Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous coefficient.The finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively.展开更多
We investigate the in-medium interparticle potential of hot gauge system with bound states by employing the QED and scalar QED coupling. At the finite temperature an oscillatory behavior of the potential has been foun...We investigate the in-medium interparticle potential of hot gauge system with bound states by employing the QED and scalar QED coupling. At the finite temperature an oscillatory behavior of the potential has been found as well as its variation in terms of different free parameters. We expect the competition among the parameters will lead to an appropriate interparticle potential, which could be extended to discuss the fluid properties of QGP with scalar bound states.展开更多
We have studied the effect of the third-order density fluctuations in the medium on the collective excitations in quark-gluon plasma.We show that the nonlinear response of a quark-gluon plasma medium leads to non-Abel...We have studied the effect of the third-order density fluctuations in the medium on the collective excitations in quark-gluon plasma.We show that the nonlinear response of a quark-gluon plasma medium leads to non-Abelian collective excitations.We present two kinds of non-Abelian oscillation solutions which respectively correspond to weakly and strongly nonlinear coupling of field components in the color space.We also show that the weakly nonlinear solution is similar to the Abelian-like one but has a frequency shift,which is of order g^(2)T,from the eigenfrequency.展开更多
This letter addresses a problem concerning temperature corrections to the scattering processes.Although former studies had given the temperature-dependent phase space factors in the corrections,how to derive them from...This letter addresses a problem concerning temperature corrections to the scattering processes.Although former studies had given the temperature-dependent phase space factors in the corrections,how to derive them from the first principles was not clear.In this letter,we consider this question within the formalism of thermal field dynamics.We find that if the initial and final states in scattering processes at finite temperature are constructed from the expanded vacuum states,the scattering rate in medium can be derived with the desired temperature-dependent phase space factors.展开更多
The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the Keldysh representation for the propagators.This simpliSes the ca...The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the Keldysh representation for the propagators.This simpliSes the calculation significantly and allows a Dyson resummation.The expression is used to demonstrate that potential infrared divergences are rendered harmless.We apply it to check the pressures of an ideal fermion gas and of a chemically non-equilibrated quantum chromodynamics plasma.展开更多
基金supported by National Natural Science Foundation of China under Grant Nos.10675052,10575043,and 10747135
文摘Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous coefficient.The finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively.
基金Supported by National Natural Science Foundation of China under Grant Nos. 10747135, 10675052 and 10875050
文摘We investigate the in-medium interparticle potential of hot gauge system with bound states by employing the QED and scalar QED coupling. At the finite temperature an oscillatory behavior of the potential has been found as well as its variation in terms of different free parameters. We expect the competition among the parameters will lead to an appropriate interparticle potential, which could be extended to discuss the fluid properties of QGP with scalar bound states.
基金Supported by the National Natural Science Foundation of China under Grant No.19775017.
文摘We have studied the effect of the third-order density fluctuations in the medium on the collective excitations in quark-gluon plasma.We show that the nonlinear response of a quark-gluon plasma medium leads to non-Abelian collective excitations.We present two kinds of non-Abelian oscillation solutions which respectively correspond to weakly and strongly nonlinear coupling of field components in the color space.We also show that the weakly nonlinear solution is similar to the Abelian-like one but has a frequency shift,which is of order g^(2)T,from the eigenfrequency.
基金Supported in part by the National Natural Science Foundation of China under Grand No.19775017.
文摘This letter addresses a problem concerning temperature corrections to the scattering processes.Although former studies had given the temperature-dependent phase space factors in the corrections,how to derive them from the first principles was not clear.In this letter,we consider this question within the formalism of thermal field dynamics.We find that if the initial and final states in scattering processes at finite temperature are constructed from the expanded vacuum states,the scattering rate in medium can be derived with the desired temperature-dependent phase space factors.
基金Supported by the Deutsche Forschungsgemeinschaft(DFG)the Bundesministerium fur Bildung und Forschung(BMBF)+1 种基金the National Natural Science Foundation of China under Grant No.19775017the Gesellschaft fur Schwerionenforschung(GSI).
文摘The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the Keldysh representation for the propagators.This simpliSes the calculation significantly and allows a Dyson resummation.The expression is used to demonstrate that potential infrared divergences are rendered harmless.We apply it to check the pressures of an ideal fermion gas and of a chemically non-equilibrated quantum chromodynamics plasma.
