Is gravity entropic force?
  If we assume that the source of thermodynamic system, $\rho$ and $p$, are also the source of gravity, thermal quantities, such as entropy, temperature, and chemical potential, can induce effects of gravity, or gravity can induce thermal effects. We find only for systems with constant temperature and zero chemical potential, gravity can be seen as an entropic force. The case for Newtonian approximation is discussed. 
Rong-Jia Yang
gr-qc hep-th