Neumann's law

Neumann's Law, often referred to in the context of thermodynamics and heat transfer, is typically associated with the behavior of heat conduction in materials. It states that the heat flux out of a material is proportional to the temperature gradient within that material, usually expressed mathematically by Fourier's law of heat conduction. In a broader context, the law may also refer to various principles in physics and mathematics related to von Neumann's work, such as in quantum mechanics or game theory.