Strong coupling expansion for finite temperature Yang-Mills theory in the confined phase

Understand

We perform euclidean strong coupling expansions for Yang Mills theory on the lattice at finite temperature.

• After setting up the formalism for general SU(N), we compute the first few terms of the series for the free energy density and the lowest screening mass in the case of SU(2).
• To next-to-leading order the free energy series agrees with that of an ideal gas of glueballs.
• This demonstrates that in the confined phase the quasi-particles indeed correspond to the T=0 hadron excitations, as commonly assumed in hadron resonance gas models.