Quantum equilibrium hypothesis

Quantum non-equilibrium is a concept within stochastic formulations of the De Broglie–Bohm theory of quantum physics.

In the Copenhagen interpretation, that is, the most widely used interpretation of quantum mechanics, the Born rule ${\displaystyle \rho (\mathbf {x} ,t)=|\psi (\mathbf {x} ,t)|^{2}}$ defines that ${\displaystyle \rho }$, the probability density function of a particle (that is, the probability to find the particle in the differential volume ${\displaystyle d^{3}x}$ at time t) equals the absolute square of the wave function ${\displaystyle \psi }$, and it constitutes one of the fundamental axioms of the theory.

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