Equation of State for the SU(3) Gauge Theory

Abstract

Through a detailed investigation of the $SU(3)$ gauge theory at finite temperature on lattices of various size we can control finite lattice cut-off effects in bulk thermodynamic quantities. We calculate the pressure and energy density of the $SU(3)$ gauge theory on lattices with temporal extent $N_\tau = 4$, 6 and 8 and spatial extent $N_\sigma =16$ and 32. The results are extrapolated to the continuum limit. We find a deviation from ideal gas behaviour of (15-20)\%, depending on the quantity, even at temperatures as high as $T\sim 3T_c$. A calculation of the critical temperature on lattices with temporal extent $N_\tau = 8$ and 12 and the string tension on $32^4$ lattices at the corresponding critical couplings is performed to fix the temperature scale. An extrapolation to the continuum limit yields $T_c/\sqrt{\sigma} = 0.629(3)$.Comment: 12 pages, LaTeX2e, 5 figures in a seperate uuencoded compressed file. fixed end{document

Strongly coupled quark gluon plasma (SCQGP)

“…Only difference is in Γ. SCP is widely studied by theoretical and numerical methods and EoS of SCP is parametrized as function of Γ [16]. We will show here that the same EoS with Γ for QGP, very nicely fits the lattice results on EoS of gluon [4] In Ref. [6], we attempted to explain the non-ideal behaviour seen in lattice by considering Cornel potential, Coulomb + linear confining potential, using Mayer's cluster expansion method.…”

QCD at high density/temperature

“…The theoretical uncertainty comes from varying the renormalization scale by a factor of 2 around the first Matsubara frequency 2πT . The grey bands show the results of lattice calculations [69]. Finally, the range of predictions of the BIR and ABPS hard thermal loop methods are shown.…”

The quark gluon plasma: Lattice computations put to experimental test

“…In Figure 2 we show our extraction of c s from the data in [24]. This computation is preliminary (a more detailed computation is underway), and the main uncertainty is connected with the fact that the lattice data used have finite lattice spacing artifacts which need to be compensated for.…”

“…If flow can be unambiguously identified in experiments, then the equation of state (EOS) of QCD matter becomes accessible to measurement, since it is an input to the hydrodynamical equations. The EOS, i.e., the temperature dependence of pressure (P ) , energy (E) and entropy (S) densities, have been extracted on the lattice in quenched QCD [24] as well as in QCD with two [25] or four [26] flavours of dynamical quarks. It is a remarkable lacuna that these EOS has not yet been put through the machinery of hydrodynamical codes to confront experiments [27].…”