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arXiv · 1709.04216

Lions' maximal regularity problem with H 1/ 2 -regularity in time

Mahdi Achache·El Maati Ouhabaz
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Abstract

We consider the problem of maximal regularity for non-autonomous Cauchy problems u ' (t) + A(t) u(t) = f (t), t $\in$ (0, $\tau$ ] u(0) = u 0. The time dependent operators A(t) are associated with (time dependent) sesquilinear forms on a Hilbert space H. We are interested in J.L. Lions's problem concerning maximal regularity of such equations. We give a positive answer to this problem under minimal regularity assumptions on the forms. Our main assumption is that the forms are piecewise H 1 2 with respect to the variable t. This regularity assumption is optimal and our results are the most general ones on this problem.

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Mahdi Achache, El Maati Ouhabaz. 2017-09-13. Lions' maximal regularity problem with H 1/ 2 -regularity in time. https://arxiv.org/abs/1709.04216

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