In physics, black hole thermodynamics is a set of physical relationships between the properties of black holes that stands in direct relationship to classical laws of thermodynamics. The equivalence is developed by replacing entropy with black hole horizon area and replacing temperature with black hole horizon surface gravity. Having temperature implies that a black hole must emit radiation, that is, Hawking radiation. There is no known way to verify black hole thermodynamics; it is the most widely accepted physical model that combines general relativity, quantum field theory, and thermodynamics, though Hawking's area law has already been tested by analyzing gravitational waves.
