This paper built upon work that Stephen Hawking did. "The hypothesis of gravity being an entropic force has a history that goes back to research on black hole

This paper built upon work that Stephen Hawking did. "The hypothesis of gravity being an entropic force has a history that goes back to research on black hole thermodynamics by Bekenstein and Hawking in the mid-1970s. These studies suggest a deep connection between gravity and thermodynamics." http://en.wikipedia.org/wiki/Gravity_as_an_entropic_force http://en.wikipedia.org/wiki/Gravity_as_an_entropic_force someone might be able to find a better source.