Dephasing rate SP formula

The SP formula for the dephasing rate Γ φ {\displaystyle \Gamma _{\varphi }} of a particle that moves in a fluctuating environment unifies various results that have been obtained, notably in condensed matter physics, with regard to the motion of electrons in a metal. The general case requires taking into account not only the temporal correlations but also the spatial correlations of the environmental fluctuations.

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