Speaker
Description
At high baryon chemical potential mu, the pressure of QCD allows a weak-coupling expansion in the QCD coupling parameter alpha_s. The result is currently known up to and including the full NNLO alpha_s^2, first computed in 1977 for massless quarks by Freedman and McLerran. Starting at this order, computations are complicated by the modification of particle propagation in a dense medium, which necessitates non-perturbative treatment of the so-called soft scale alpha_s^(1/2) mu. In this talk, I will describe a Hard-Thermal-Loop scheme for capturing the contributions of this scale to the weak-coupling expansion, and show how to use it to determine the leading-logarithm contribution at NNNLO: alpha_s^3 ln(alpha_s)^2. This result is the first improvement to the pressure of massless cold quark matter in 40 years. I will also say a few words about current work being undertaken to expand this result to the subleading linear logarithm: alpha_s^3 ln(alpha_s).
