Related papers: HTL Perturbation Theory to Two Loops
We propose a gauge-invariant and manifestly UV finite resummation of the physics of hard thermal/dense loops (HTL/HDL) in the thermodynamics of the quark-gluon plasma. The starting point is a simple, effectively one-loop expression for the…
We perform a two-loop calculation in Light Cone Perturbation Theory (LCPT) to evaluate the next-to-leading order nonsinglet splitting function. Our calculation demonstrates the methodology and feasibility of performing higher order…
We present results of a three-loop hard-thermal-loop perturbation theory calculation of the thermodynamical potential of a finite temperature and baryon chemical potential system of quarks and gluons. We compare the resulting pressure and…
We evaluate the second and fourth order quark number susceptibilities in hot QCD using two variations of resummed perturbation theory. On one hand, we carry out a one-loop calculation within hard-thermal-loop perturbation theory, and on the…
Two recent attempts for overcoming the poor convergence of the perturbation expansion of the thermodynamic potentials of QCD are discussed: an HTL-adaption of ``screened perturbation theory'' and approximately self-consistent HTL…
In hot gauge theories, perturbation theory at the scale of the Debye screening mass requires the resummation of the so-called hard thermal loops, which corresponds to using an effective action obtained by integrating out the modes with…
In HTL perturbation theory we obtain leading order quark number susceptibility as a response to an external disturbance, viz., chemical potential (\mu) that generates density fluctuation, which is related to the correlation function through…
We demonstrate that at finite density and sufficiently high temperatures, phase-quenched (PQ) lattice simulations combined with perturbation theory provide a new precision approach to determining the thermodynamics of QCD across a wide arc…
High-order perturbative calculations for thermodynamic quantities in QCD are complicated by the physics of dynamical screening that affects the soft, long-wavelength modes of the system. Here, we provide details for the evaluation of this…
We apply the method of \underline{zeta} functions, together with the $n_\mu^*$-prescription for the temporal gauge, to evaluate the thermodynamic pressure in QCD at finite temperature $T$. Working in the imaginary-time formalism and…
Considering recently developed Hard Thermal Loop perturbation theory that takes into account the effect of the variation of the external field through the fluctuations of a conserved quantity we calculate the temporal component of the…
We present compact expressions for the power corrections to the hard thermal loop (HTL) Lagrangian of QED in $d$ space dimensions. These are corrections of order $(L/T)^2$, valid for momenta $L \ll T$, where $T$ is the temperature. In the…
The QCD pressure is a most fundamental quantity, for which lattice data is available up to a few times the critical temperature $T_c$. Perturbation theory, even at very high temperatures, has serious convergence problems. Combining…
The Hard Thermal Loop expansion, is an attractive theory, but it reveals difficulties when one uses it as a perturbative scheme. To illustrate this we use the HTL expansion to calculate the two loop corrections for soft virtual photons. The…
We report progress towards computing the heavy quark momentum diffusion coefficient from the correlator of two chromo-electric fields attached to a Polyakov loop in pure SU(3) gauge theory. Using a multilevel algorithm and tree-level…
I review recent developments in QCD thermodynamics and collective excitations from the hard-thermal-loop effective theory. I begin by motivating the discussion with open questions from heavy-ion collisions. I then discuss a…
We compute the pressure of a finite density quark-gluon plasma at zero temperature to leading order in hard-thermal-loop perturbation theory, which includes the fermionic excitations and Landau damping. The result is compared with the…
We calculate second- and fourth-order cumulants of conserved charges in a temperature range stretching from the QCD transition region towards the realm of (resummed) perturbation theory. We perform lattice simulations with staggered quarks;…
Dimensional reduction is a key issue in finite temperature field theory. For example, when following the QCD Free Energy from low to high scales across the critical temperature, ultrasoft degrees of freedom can be captured by a 3d SU(3)…
Current results in high temperature gauge theories obtained in the context of the perturbative method of resumming hard thermal loops are reviewed. Beyond leading order properties of the gluon excitation, and the recent (controversial)…