相关论文: The Three-Loop Free Energy for Pure Gauge QCD
We study the $O(N)$ vector model for scalars with quartic interaction at large $N$ on $S^1\times S^2$ without the singlet constraint. The non-trivial fixed point of the model is described by a thermal mass satisfying the gap equation at…
We discuss the electroweak phase-transition in the early universe, using non-perturbative flow equations for a computation of the free energy. For a scalar mass above $\sim 70$ GeV, high-temperature perturbation theory cannot describe this…
We study the graviton self-energy function in a general gauge, using a hard thermal loop expansion which includes terms proportional to T^4, T^2 and log(T). We verify explicitly the gauge independence of the leading T^4 term and obtain a…
We investigate an effective model for the finite temperature restoration phase transition of the electroweak theory. It is obtained by dimensional reduction of the $3+1$ dimensional full theory and by subsequent integration over all static…
In many extensions of the Standard Model, finite temperature computations are complicated by a hierarchy of zero temperature mass scales, in addition to the usual thermal mass scales. We extend the standard thermal resummations to such a…
A lower bound is derived on the free energy (per unit volume) of a homogeneous Bose gas at density $\rho$ and temperature $T$. In the dilute regime, i.e., when $a^3\rho \ll 1$, where $a$ denotes the scattering length of the pair-interaction…
We consider a possible `deformation' of the trace of the heat kernel on odd dimensional spheres, motivated by the calculation of the free energy of a scalar field on a discretized circle. By using an expansion in terms of the modified…
Recently several workers have attempted determinations of the so-called magnetic mass of d=3 non-Abelian gauge theories through a one-loop gap equation, using a free massive propagator as input. Self-consistency is attained only on-shell,…
It is shown that three series of diagrams entering the calculation of some hot $QCD$ process, are mass (or collinear) singularity free, indeed. This generalizes a result which was recently established up to the third non trivial order of…
In this paper, we study the free energy of the directed polymer on a cylinder of radius $L$ with the inverse temperature $\beta$. Assuming the random environment is given by a Gaussian process that is white in time and smooth in space, with…
We compute the free energy density of QCD to order $\alpha_s$ at very high density and non-zero quark masses. The counterterms needed to renormalise the theory to order $\alpha_s$ is same as the vacuum (non-zero density) theory. We…
Recent calculations in one-loop and Gaussian appro- ximation, using the so-called autonomous renormalization scheme, indicate a comparatively massive, narrow Higgs excitation at about 2 TeV. Here I show that this result qualitatively…
We consider the interacting Bose gas in the thermodynamic limit in a large box in $\R^d$ at positive temperature $1/\beta\in(0,\infty)$ with particle density $\sim\rho\in(0,\infty)$. We follow a path-integral approach and adopt from \cite…
The generally accepted ``triviality'' of $\lambda\Phi^4$ theories does not forbid Spontaneous Symmetry Breaking but implies a trivially free shifted field which becomes effectively governed by a quadratic hamiltonian. As a consequence, one…
The pinch technique (PT) is applied to obtain the gauge-independent resummed gluon self-energy in a hot Yang-Mills gas. Calculation is performed at one- loop level in linear gauges which preserve rotational invariance and the res ummed…
Nonlinear density response theory is revisited focusing on the harmonically perturbed finite temperature uniform electron gas. Within the non-interacting limit, brute force quantum kinetic theory calculations for the quadratic, cubic,…
In the unitary gauge the unphysical degrees of freedom of spontaneously broken gauge theories are eliminated. The Feynman rules are simpler than in other gauges, but it is non-renormalizable by the rules of power counting. On the other…
The "basketball diagram" is a three-loop vacuum diagram for a scalar field theory that cannot be expressed in terms of one-loop diagrams. We calculate this diagram for a massive scalar field at nonzero temperature, reducing it to…
We present a brief review of the non-Abelian tensor gauge field theory and analyze its free field equations for lower rank gauge fields when the interaction coupling constant tends to zero. The free field equations are written in terms of…
Massive field theory at fixed dimension d<4 is combined with the minimal subtraction scheme to calculate the amplitude functions of thermodynamic quantities for the O(n) symmetric phi^4 model below T_c in two-loop order. Goldstone…