We extend our work on QCD thermodynamics with 2+1 quark flavors at nonzero
chemical potential to finer lattices with Nt​=6. We study the equation of
state and other thermodynamic quantities, such as quark number densities and
susceptibilities, and compare them with our previous results at Nt​=4. We
also calculate the effects of the addition of the charm and bottom quarks on
the equation of state at zero and nonzero chemical potential. These effects are
important for cosmological studies of the early Universe.Comment: 27 pages, 17 figures. Some small text and figure change