Random walks and encounters

And with the wine no longer in bottles but in their heads, they went out to the street. 

Let us consider now Just a pair of immobile point particles A and B which are chemically interacting with each other (that is, a given pair AB transforms into another pair A B )- This pair reaction could be described by the simplest decay law exp(—f/r), their lifetime r = r(r) is defined by their 

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