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Uniqueness of very weak solutions for a fractional filtration equation

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 Added by Gabriele Grillo
 Publication date 2019
  fields
and research's language is English




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We prove existence and uniqueness of distributional, bounded, nonnegative solutions to a fractional filtration equation in ${mathbb R}^d$. With regards to uniqueness, it was shown even for more general equations in [19] that if two bounded solutions $u,w$ of (1.1) satisfy $u-win L^1({mathbb R}^dtimes(0,T))$, then $u=w$. We obtain here that this extra assumption can in fact be removed and establish uniqueness in the class of merely bounded solutions, provided they are nonnegative. Indeed, we show that a minimal solution exists and that any other solution must coincide with it. As a consequence, distributional solutions have locally-finite energy.



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