Glueballs and the Yang-Mills plasma in aT-matrix approach

Abstract

The strongly coupled phase of Yang-Mills plasma with arbitrary gauge group is studied in a T matrix approach. The existence of lowest-lying glueballs, interpreted as bound states of two transverse gluons (quasiparticles in a many-body setup), is analyzed in a nonperturbative scattering formalism with the input of lattice-QCD static potentials. Glueballs are actually found to be bound up to 1.3 T c . Starting from the T-matrix, the plasma equation of state is computed by resorting to a formulation of statistical mechanics (Dashen et al.) and favorably compared to quenched lattice data. Special emphasis is put on SUðNÞ gauge groups, for which analytical results can be obtained in the large-N limit, and predictions for a G 2 gauge group are also given in this work.

The SUSY Yang–Mills plasma in a T-matrix approach

“…Such a formulation is particularly well suited for systems whose microscopic constituents behave according to relativistic quantum mechanics: In our framework, the deconfined phase is seen as a strongly-interacting gas of gluons and gluinos propagating in the plasma. Note that the approach described in [6] has already proven to reproduce accurately the current lattice data concerning the EoS of ordinary YM theory for the gauge groups SU(N).…”

“…III. Note that more detailed explanations about this approach can be found in [6]. The results obtained in the strongly-coupled stage of the deconfined phase, that is for temperatures just above T c , are presented and discussed in Sec.…”

“…First, there still exists a firstorder deconfining phase transition with the gauge groups G 2 , SU(N > 3), SP (2) and E 7 [2][3][4]. Second, the equation of state (EoS) above the deconfining temperature T c , appears to be nearly independent of the gauge group once normalized to the Stefan-Boltzmann pressure [4][5][6]. Below T c , the EoS seems to be compatible with a Hagedorn-type density of state with the Hagedorn temperature T h playing the role of T c [7,8].…”

“…The main purpose of the present work is to study the thermodynamic features of the deconfined phase of N = 1 SUSY YM theory by resorting to the formalism described in [6]. This formalism is based on a T -matrix approach that allows to model the bound states and scattering states of the system in an unified way [21].…”

Lattice simulations of G2-QCD at finite density

“…The theory is a gauge theory with fermionic baryons and fundamental quarks [1,2] and it can be simulated without sign problem at finite density and temperature. Unlike other QCD-like theories such as adjoint QCD or two color QCD, for example, its properties in the quenched case are very similar to those of QCD [3][4][5][6][7][8]. Although the center of G 2 is trivial, it shows a first order deconfinement transition which has quite interesting implications for the role of the center symmetry in QCD as reviewed in [9] for Lattice 2012.…”