Entropic gravity is a hypothesis in modern physics that describes gravity as an entropic force; not a fundamental interaction mediated by a particle, but a probabilistic consequence of physical systems' tendency to increase their entropy.
The probabilistic description of gravity has a history that goes back at least to Richard Feynman in the early 1960's, and to research on black hole thermodynamics by Bekenstein and Hawking in the mid-1970s. These studies suggest a deep connection between gravity and thermodynamics, which describes the behavior of heat and gases. In 1995, Jacobson demonstrated that the Einstein equations describing relativistic gravitation can be derived by combining general thermodynamic considerations with the equivalence principle. Subsequently, other physicists began to explore links between gravity and entropy.
Erik Verlinde's theory
In 2009, Erik Verlinde disclosed a conceptual theory that describes gravity as an entropic force. On January 6, 2010 he published a preprint of a 29 page paper titled On the Origin of Gravity and the Laws of Newton. (It was published in April 2011). Reversing the logic of over 300 years, it argued that gravity is a consequence of the laws of thermodynamics. This theory combines the thermodynamic approach to gravity with Gerardus 't Hooft's holographic principle. If proven correct, this implies gravity is not a fundamental interaction, but anemergent phenomenon which arises from the statistical behavior of microscopic degrees of freedom encoded on a holographic screen. The paper drew a variety of responses from the scientific community. Andrew Strominger, a string theorist at Harvard said “Some people have said it can’t be right, others that it’s right and we already knew it — that it’s right and profound, right and trivial."
Verlinde's article also attracted a large amount of media exposure, and led to immediate follow-up work in cosmology, the dark energy hypothesis, cosmological acceleration, cosmological inflation, and loop quantum gravity. Also, a specific microscopic model has been proposed that indeed leads to entropic gravity emerging at large scales.
Verlinde’s theory is criticized  on the basis that it fails to reproduce gravitational bound states of neutron observed in the experiments with ultracold neutrons
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