Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2006-09-19
Phys.Rev.D75:084003,2007
Physics
High Energy Physics
High Energy Physics - Theory
v4: Revtex, 18 pages, to appear in PRD
Scientific paper
10.1103/PhysRevD.75.084003
It is shown that the differential form of Friedmann equation of a FRW universe can be rewritten as a universal form $dE = TdS + WdV$ at apparent horizon, where $E$ and $V$ are the matter energy and volume inside the apparent horizon (the energy $E$ is the same as the Misner-Sharp energy in the case of Einstein general relativity), $W=(\rho-P)/2$ is the work density and $\rho$ and $P$ are energy density and pressure of the matter in the universe, respectively. From the thermodynamic identity one can derive that the apparent horizon has associated entropy $S= A/4G$ and temperature $T = \kappa / 2\pi$ in Einstein general relativity, where $A$ is the area of apparent horizon and $\kappa$ is the surface gravity at apparent horizon. We extend our procedure to the Gauss-Bonnet gravity and more general Lovelock gravity and show that the differential form of Friedmann equations in these gravities can also be rewritten to thee universal form $dE = TdS + WdV$ at the apparent horizon with entropy $S$ being given by expression previously known via black hole thermodynamics.
Akbar M. M.
Cai Rong-Gen
No associations
LandOfFree
Thermodynamic Behavior of Friedmann Equation at Apparent Horizon of FRW Universe does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Thermodynamic Behavior of Friedmann Equation at Apparent Horizon of FRW Universe, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermodynamic Behavior of Friedmann Equation at Apparent Horizon of FRW Universe will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-466072