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arXiv · 2108.05757

On symmetric div-quasiconvex hulls and divsym-free $\mathrm{L}^\infty$-truncations

Linus Behn·Franz Gmeineder·Stefan Schiffer
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Abstract

We establish that for any non-empty, compact set $K\subset\mathbb{R}_{\mathrm{sym}}^{3\times 3}$ the $1$- and $\infty$-symmetric div-quasiconvex hulls $K^{(1)}$ and $K^{(\infty)}$ coincide. This settles a conjecture in a recent work of Conti, M\"{u}ller and Ortiz (Symmetric Div-Quasiconvexity and the Relaxation of Static Problems. Arch. Ration. Mech. Anal. 235(2):841-880) in the affirmative. As a key novelty, we construct an $\mathrm{L}^{\infty}$-truncation that preserves both symmetry and solenoidality of matrix-valued maps in $\mathrm{L}^{1}$.

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Linus Behn, Franz Gmeineder, Stefan Schiffer. 2021-08-12. On symmetric div-quasiconvex hulls and divsym-free $\mathrm{L}^\infty$-truncations. https://arxiv.org/abs/2108.05757

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