emergentgravity

Emergent gravity refers to a family of theoretical ideas in which gravity is not a fundamental interaction, but arises as a macroscopic, collective phenomenon from more basic microscopic degrees of freedom. In these frameworks, spacetime geometry and gravitational dynamics emerge from underlying physics, such as quantum information, thermodynamics, or condensate-like behavior, rather than being built into the basic laws at the smallest scales.

One prominent approach is entropic gravity, most associated with Erik Verlinde. In this view, gravity is an entropic force resulting from changes in information associated with the positions of matter on holographic screens. Some versions of the proposal claim to reproduce aspects of galaxy rotation and cosmic acceleration without invoking dark matter, though these claims are contested and not universally accepted within the community.

Other lines of work emphasize thermodynamic aspects of spacetime. For example, the idea that Einstein’s field equations can be derived from thermodynamic relations applied to local horizons, or from considerations of entropy, temperature, and information content, is interpreted as suggesting gravity is an emergent, equation-of-state property rather than a fundamental force.

Earlier ideas, such as Sakharov’s induced gravity, proposed that gravity could arise from quantum fluctuations of matter fields in curved spacetime, offering a historical precursor to emergent viewpoints. In broader contexts, holography and gauge/gravity duality in string theory illustrate how gravitational dynamics can emerge from lower-dimensional quantum systems.

The status of emergent gravity remains debated. It provides conceptual insight into how gravity might arise from deeper physics, but it has yet to achieve broad empirical success or consensus as a complete replacement for general relativity. It is often discussed as complementary to, rather than a replacement for, mainstream approaches to quantum gravity.