Smooth Density Eld of Catalytic Super-brownian Motion
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چکیده
Given an (ordinary) super-Brownian motion (SBM) % on R d of dimension d = 2; 3; we consider a (catalytic) SBM X % on R d with \local branching rates" %s(dx). We show that X % t is absolutely continuous with a density function % t ; say. Moreover, there exists a version of the map (t; z) 7 ! % t (z) which is C 1 and solves the heat equation oo the catalyst %, more precisely, oo the (zero set of) closed support of the time-space measure ds %s(dx): Using self-similarity, we apply this result to answer the question of the long-term behavior of X % in dimension d = 2 : If % and X % start with a Lebesgue measure, then X % T converges (persistently) as T ! 1 towards a random multiple of Lebesgue measure. Smooth density eld for catalytic SBM
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تاریخ انتشار 1999