2011/10/04 by Juhee Hong, Hong, Juhee
Physics and Astronomy · #FOS: Physical sciences #Nuclear Theory (nucl-th) #nucl-th
paper · pdf · doi:10.48550/arxiv.1110.0809
8 pages, 6 figures, prepared for proceedings of DPF 2011 Conference, Providence, RI, August 8-13, 2011
arxiv created 2011/10/04 · arxiv updated 2011/10/05
We present the energy density and flux distribution of a heavy quark moving through high temperature QCD plasmas and compare them with those in the strongly coupled N = 4 SYM plasma. The Boltzmann equation is reformulated as a Fokker-Planck equation at the leading log approximation and is solved numerically with nontrivial boundary conditions in momentum space. We use kinetic theory and perform a Fourier transform to calculate the energy and momentum density in position space. The angular distributions exhibit the transition to the ideal hydrodynamics and are analyzed with the first and second order hydrodynamic source. The AdS/CFT correspondence allows the same calculation at strong coupling. Compared to the kinetic theory results, the energy-momentum tensor is better described by hydrodynamics even after accounting for the differences in the shear viscosities. We argue that the difference between the Boltzmann equation and the AdS/CFT correspondence comes from the second order hydrodynamic coefficient τπ which is generically large compared to the shear length in a theory based on the Boltzmann equation.