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arXiv · 1711.07834

A counterexample related to the regularity of the $p$-Stokes problem

Martin Křepela·Michael Růžička
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Abstract

In this paper we construct a solenoidal vector field $\mathbf{u}$ belonging to $W^{2,q}(Ω)\cap W^{1,s}_0(Ω)$, $s \in (1,\infty)$, $q \in (1,n)$, such that $(1+|\mathbf{Du}|)^{p-2}$, $p\in (1,2)\cup(2,\infty)$, does not belong to the Muckenhoupt class $A_\infty(Ω)$. Thus, one cannot use the Korn inequality in weighted Lebesgue spaces to prove the natural regularity of the $p$-Stokes problem.

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Martin Křepela, Michael Růžička. 2017-11-21. A counterexample related to the regularity of the $p$-Stokes problem. https://arxiv.org/abs/1711.07834

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