Related papers: Quantum corrections to eta/s
The elliptic flow $v_2$ and the ratio of the shear viscosity over the entropy density, $\eta/s$, of gluon matter are calculated from the perturbative QCD (pQCD) based parton cascade Boltzmann approach of multiparton scatterings. For Au+Au…
This work is a collection of initial calculations and formal considerations within the Salpeter-Sucher exact equal-time relativistic quantum electrodynamics framework. The calculations are carried out as preparation for the computation of…
We calculate the shear viscosity to entropy density ratio in pure SU(N) Yang-Mills theory below the critical temperature using the strong coupling expansion. The result for the eta/s ratio for temperatures around the phase transition is…
We calculate chromo-electric and chromo-magnetic correlators in quenched QCD at $1.5T_c$ and $10^4 T_c$ with the aim to estimate the heavy quark diffusion coefficient at leading order in the inverse heavy quark mass expansion, $\kappa_E$,…
Electroweak Sudakov logarithms at high energy, of the form alpha/sin^2 theta_W^n log^m s/M_{Z,W}^2, are summed using effective theory (EFT) methods. The exponentiation of Sudakov logarithms and factorization is discussed in the EFT…
Front form dynamics is not a manifestly rotational invariant formalism. In particular, the requirement of an invariance under rotations around the transverse axes is difficult to fulfill.In the present work it is investigated, to which…
We present the full details of a calculation at next-to-leading order of the momentum diffusion coefficient of a heavy quark in a hot, weakly coupled, QCD plasma. Corrections arise at O(g_s); physically they represent interference between…
In this article we study, via analytical methods, $1/Q$ non-perturbative power corrections to event shape mean values, addressing in particular the question of their interplay with soft perturbative emissions. Specifically we point out that…
Within the nonrelativistic QCD (NRQCD) factorization framework, we calculate the exclusive decay process \eta_b \to J/\psi J/\psi to next-to-leading order in the strong coupling constant, while at leading order in charm quark relative…
We consider the four-point correlator of the stress-energy tensor multiplet in ${\cal N}=4$ SYM. In the planar limit and at large 't Hooft coupling such correlator is given by the corresponding holographic correlation function in IIB…
Next-to-Leading-Order(NLO) QCD corrections to J/jpsi plus eta_c production in e+e- annihilation at sqrt{s}=10.6 GeV is calculated in this paper, and an analytic result is obtained. By choosing proper physical parameters, a K factor (ratio…
We present the energy density and flux distribution of a heavy quark moving through high temperature QCD plasmas and compare them with those in the strongly coupled N = 4 SYM plasma. The Boltzmann equation is reformulated as a Fokker-Planck…
We explain a method for computing the bulk viscosity of strongly coupled thermal plasmas dual to supergravity backgrounds supported by one scalar field. Whereas earlier investigations required the computation of the leading dissipative term…
We explore the influence of a temperature-dependent shear viscosity over entropy density ratio $\eta/s$ on the azimuthal anisotropies v_2 and v_4 of hadrons at various rapidities. We find that in Au+Au collisions at full RHIC energy,…
We present, for the first time, simultaneous determination of shear viscosity ($\eta$) and entropy density ($s$) and thus, $\eta/s$ for equilibrated nuclear systems from $A$ $\sim$ 30 to $A$ $\sim$ 208 at different temperatures. At finite…
We consider a rotating quark-antiquark $(q\bar{q})$ pair in $\mathcal{N}=4$ thermal plasma. By using AdS/CFT correspondence, the properties of this system have been investigated. We study variation of rotating string radius at the boundary…
We investigate the robustness of the Araki-Lieb inequality in a two-dimensional (2D) conformal field theory (CFT) on torus. The inequality requires that $\Delta S=S(L)-|S(L-\ell)-S(\ell)|$ is nonnegative, where $S(L)$ is the thermal entropy…
We compute double-logarithmically enhanced corrections to $\widehat{q}$ at relative order $O(g^2)$ in the setting of a weakly coupled quark-gluon plasma, observing how the thermal scale affects the region of phase space, which gives rise to…
In this paper based on the basic principles of gauge/gravity duality we compute the hall viscosity to entropy ratio in the presence of various higher derivative corrections to the dual gravitational description embedded in an asymptotically…
We present a new computation of S-wave color-singlet nonrelativistic QCD matrix elements for the J/psi and the eta_c. We compute the matrix elements of leading order in the heavy-quark velocity v and the matrix elements of relative order…