# Program of talks

 Date Session 09:00-10:00 11:00-12:00 Session 14:00-15:00 16:00-17:00 15 Developments in field theory Aarts Bodeker L Lattice results Mukherjee Ray 16 Developments in field theory Aarts Bodeker U Flow Bhalerao 17 Transport coefficients Nakamura Gupta N Discussion 18 Pressure and strangeness Blaizot Gavai C Discussion Stamatescu 19 RHIC initial state Ravishankar Srivastava H Discussion

*) Each talk is followed by a discussion session (duration about 30 minutes) and a coffee break.

## Gert Aarts

Quantum and classical fields far from equilibrium: an overview
The current status of quantum and classical fields far from equilibrium is reviewed. Among other things, I'll discuss the limitations of mean-field approximations, the importance of classical field theory to benchmark truncation schemes, and the recent progress made using the 2PI effective action.
Close to equilibrium: transport coefficients and spectral functions
Some recent results on transport coefficients and spectral functions in thermal field theory are presented. I'll discuss transport coefficients from a diagrammatic approach, the relevance of Ward identities, the relation between transport coefficients and the 2PI effective action, and the use of lattice QCD. I'll also mention a nonperturbative approach to the computation of spectral functions in the classical limit.

## Rajeev Bhalerao

Anisotropic flow in relativistic heavy-ion collisions
I will introduce the subject of Anisotropic Flow with a particular emphasis on flow as a probe of equilibration of the matter produced in relativistic heavy-ion collisions. I will then describe our recent work on the question of what is the best way to analyse the flow data and extract the genuine flow free of spurious effects. I will also try to summarise the experimental and theoretical status of the field.

## Jean-Paul Blaizot

Thermodynamics of the high temperature QGP
I describe weak coupling calculations of high temperature QGP thermodynamics. The failure of perturbation theory and the need for resummation is shown. The skeleton graph expansion and an approximately self-consistent treatment which gives the entropy of the QGP is explained.

## Dietrich Bodeker

Quantum transport and Yang-Mills fields
I describe some recent developments in close to equilibrium field theory. For non-abelian gauge fields there are strongly coupled field modes even in the limit of weak gauge couplings. Using perturbation theory and 'renormalization group' techniques one can disentangle the dynamics of weakly and strongly coupled degrees of freedom and obtain effective theories for the strongly coupled ones. I also discuss the possibilities for lattice simulations of these effective theories.

## Rajiv Gavai

The Wroblewski parameter from lattice QCD
Enhancement of strangeness production has since long been proposed as a promising signal of quark-gluon plasma production. A convenient indicator for it is the Wroblewski parameter which has been shown to be about a factor two higher in heavy ion collisions. Using a method proposed by us earlier, lattice QCD results for the Wroblewski parameter have been obtained from our simulations of QCD with two light quarks both below and above the chiral transition. Our first principles based and parameter free result for the high temperature phase agrees will with the A-A data. Our results also indicate lower value for the low temperature phase which seems to need bigger lattices to pin it down precisely.

## Sourendu Gupta

The electrical conductivity of the QCD plasma: a lattice study
The electrical conductivity in the hot phase of the QCD plasma is extracted from a quenched lattice measurement of the Euclidean time vector correlator for 1.5<T/Tc<3. The spectral density in the vicinity of the origin is analysed using a method specially adapted to this region, and a peak at small energies is seen. The vector susceptibility is then used to extract the electrical conductivity and make a continuum extrapolation. This allows us to predict the soft photon emissivity of the QCD plasma.

## Swagato Mukherjee

The speed of sound in the QCD plasma
We report the continuum limit of the speed of sound in a QCD plasma immediately for 1.5<T/Tc<3. The results are 20-25% lower than for an ideal gas in the full range of temperature. We also report the specific heat at constant volume in the same range of temperature. The lattice measurements are made at lattice spacings small enough for the perturbative beta-function to suffice.

## Atsushi Nakamura

Lattice QCD approach for finite density and finite temperature system
We report our works to understand QCD dynamics at finite temperature and density. Since such system may be realized in high energy heavy ion collisions and inside nuclear matter in laboratories, we investigate mainly around regions which can be covered in such experiments. We discuss hadron mass behavior around $(T=T_c, \mu=0)$ including both pole and screening masses, gluon screening mass at $T=T_c \sim 5T_c$, and QGP transport coefficients. We briefly discuss other approaches to understand QCD at high density.

## V. Ravishankar

Production mechanism for quark-gluon plasma in heavy-ion collisions
In this talk, I outline a framework to describe the production process of quarks and gluons in heavy ion collisions. Based on simple and yet general considerations, the mechanism that we propose is shown to incorporate the dynamical nature of the color charge, the non-Markovian nature of production, and the dynamical role played by the vacuum. As illustrations, the production rate in the compact part of the phase space (corresponding to the color) and the configuration space will be discussed.

## Rajarshi Ray

Taylor expansion in chemical potential: the Wroblewski parameter
In this talk, I present a systematic Taylor expansion of the quark condensate with chemical potential. A Maxwell relation then allows us to connect this with the mass dependence of the Wroblewski parameter.