http://arxiv.org/abs/1912.00252
Being inspired by Verlinde’s proposal that general relativistic gravity has a thermodynamic origin as an entropic force, Newtonian gravity is reexamined in view of nonequilibrium thermodynamics. Here, firstly, an unspecified scalar field potential is introduced and treated as a thermodynamic variable on an equal footing with the fluid variables. Then, the effects of irreversibility on the field are explored through the analysis of the entropy production rate in the linear regime. Remarkably, the second law of thermodynamics imposes a stringent constraint on the allowable field, which turns out to be of gravity. The resulting field equation for the gravitational potential contains a dissipative term originating from irreversibility. It is found that the system relaxes to the conventional theory of Newtonian gravity up to a certain spatial scale (typically the solar scale), whereas on the larger scale (such as the galaxy scale) a potential needed in Modified Newtonian Dynamics (MOND) naturally appears. A comment is made on an implication of the result to the astrophysical phenomenon regarding dark matter.
P. Ván and S. Abe
Tue, 3 Dec 19
25/90
Comments: 18 pages, 1 figure