In recent years considerable progress has been made in understanding QCD at finite temperature using lattice simulations. Calculations of bulk thermodynamic quantities have been done in the realistic case of 2+1 flavors with sufficiently small quark masses using different versions of improved staggered actions [ 1, 2, 3, 4, 5]. This reduces or can even eliminate the uncertainty of extrapolation...

We consider various special cases of gluon condensates at finite temperature. The gluon condensate for an ideal gas of gluons with a given vacuum expectation value is introduced for the sake of comparison with that calculated using the recent finite temperature lattice gauge simulations for a pure Yang-Mills SU(3) gauge theory at the known critical temperature. We extend this comparison using t...

We derive the semiclassical series for the partition function of a onedimensional quantum-mechanical system consisting of a particle in a singlewell potential. We do this by applying the method of steepest descent to the path-integral representation of the partition function, and we present a systematic procedure to generate the terms of the series using the minima of the Euclidean action as th...

We apply the δ-expansion perturbation scheme to the λφ4 self-interacting scalar field theory in 3+1 D at finite temperature. In the δ-expansion the interaction term is written as λ(φ2)1+δ and δ is considered as the perturbation parameter. We compute within this perturbative approach the renormalized mass at finite temperature at a finite order in δ. The results are compared with the usual loop-...

In the last years, much effort has been paid to experimentally detect the quark-gluon plasma (QGP) in heavy-ion collisions. In these experiments, precise theoretical inputs about the nature of the transition and the equation of state (EOS) of QGP are indispensable to unambiguously identify the signal of QGP. Here, lattice QCD provides us with the most powerful method to compute thermodynamic pr...

In this the second part of a theoretical study of the thermal properties of crystalline-SiC, the thermal conductivity is calculated by using molecular dynamics simulation to evaluate directly the heat current correlation function and thus obtain the conductivity through the Green-Kubo expression in linear response theory. Adopting the same empirical potential model and the temperature scaling m...