Friedmann equations from nonequilibrium thermodynamics of the Universe: A unified formulation for modified gravity

Friedmann Equations of FRW Universe in Scalar - tensor Gravity , f ( R ) Gravity and First Law of Thermodynamics

In the paper, hep-th/0501055 (R. it is shown that by applying the first law of thermodynamics to the apparent horizon of an FRW universe and assuming the geometric entropy given by a quarter of the apparent horizon area, one can derive the Friedmann equations describing the dynamics of the universe with any spatial curvature; using the entropy formula for the static spherically symmetric black ...

First Law of Thermodynamics and Friedmann Equations of Friedmann-Robertson-Walker Universe

Applying the first law of thermodynamics to the apparent horizon of a FriedmannRobertson-Walker universe and assuming the geometric entropy given by a quarter of the apparent horizon area, we derive the Friedmann equations describing the dynamics of the universe with any spatial curvature. Using entropy formulae for the static spherically symmetric black hole horizons in Gauss-Bonnet gravity an...

Friedmann Universe in a Quantum Gravity Model

Friedmann Equations of FRW Universe in Scalar - tensor Gravity , f ( R ) Gravity and First Law of

In the paper, hep-th/0501055 (R. it is shown that by applying the first law of thermodynamics to the apparent horizon of an FRW universe and assuming the geometric entropy given by a quarter of the apparent horizon area, one can derive the Friedmann equations describing the dynamics of the universe with any spatial curvature; using the entropy formula for the static spherically symmetric black ...

A Parameterized Post-Friedmann Framework for Modified Gravity

We develop a parameterized post-Friedmann (PPF) framework which describes three regimes of modified gravity models that accelerate the expansion without dark energy. On large scales, the evolution of scalar metric and density perturbations must be compatible with the expansion history defined by distance measures. On intermediate scales in the linear regime, they form a scalar-tensor theory wit...