“…The lifetime of the metastable states is related to the Kramers escape rate formula which can be derived from the theory of instantons [ 70 ]. To the best of our knowledge, the stochastic Smoluchowski Equation ( 9 ) was first written down in van Kampen’s book [ 71 ] (p. 349) referring to the papers of van Vliet [ 72 , 73 ] in 1971; this is the oldest reference to that equation that we have found. It then appeared in different domains of physics such as the theory of simple liquids [ 63 , 74 , 75 , 76 , 77 , 78 ], the kinetic theory of adsorbates [ 25 ], systems with long-range interactions [ 14 ], 2D Brownian vortices [ 45 ], bacterial populations undergoing chemotaxis [ 79 ], nucleation [ 48 ], self-gravitating Brownian particles [ 70 ], the BMF model [ 49 ], etc.…”