Recent content by odd-socks

its to look at equations for rhodot (d rho/dt) and Hdot (dH/dt) so solve as a dynamical system for rho and H

I'm aware that the equation of state for a perfect fluid (when considering single fluid cosmology) is p=w*rho However I've come across an equation of state of p=w*rho - xi*H, H being Hubble's parameter. However I cannot find an explanation of why you can put this in? Can anyone explain this...