Review of Emergent Gravity

The idea that gravity may not be a fundamental interaction but rather an emergent phenomenon has gained increasing attention in recent decades. Building on the thermodynamical properties of spacetime horizons, various approaches suggest that Einstein’s equations can be interpreted as emergent relations, analogous to equations of state. In this review, we examine the main developments in this field, focusing on two complementary perspectives. The first is the thermodynamical approach, which connects entropy, temperature, and the Einstein field equations through horizon thermodynamics and holographic principles. The second is Verlinde’s formulation of emergent gravity, where gravity is understood as an entropic force associated with information stored on holographic screens, with potential implications for dark matter and dark energy. Finally, we discuss recent developments based on the transactional interpretation of quantum mechanics, which attempt to provide a physical basis for emergent gravity. Our aim is to provide a coherent overview of these ideas, highlighting both their conceptual appeal and open challenges.