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arXiv · 1902.08437

Random finite-difference discretizations of the Ambrosio-Tortorelli functional with optimal mesh size

Annika Bach·Marco Cicalese·Matthias Ruf
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Abstract

We propose and analyze a finite-difference discretization of the Ambrosio-Tortorelli functional. It is known that if the discretization is made with respect to an underlying periodic lattice of spacing $\delta$, the discretized functionals $\Gamma$-converge to the Mumford-Shah functional only if $\delta\ll\varepsilon$, $\varepsilon$ being the elliptic approximation parameter of the Ambrosio-Tortorelli functional. Discretizing with respect to stationary, ergodic and isotropic random lattices we prove this $\Gamma$-convergence result also for $\delta\sim\varepsilon$, a regime at which the discretization with respect to a periodic lattice converges instead to an anisotropic version of the Mumford-Shah functional.

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Annika Bach, Marco Cicalese, Matthias Ruf. 2019-02-22. Random finite-difference discretizations of the Ambrosio-Tortorelli functional with optimal mesh size. https://arxiv.org/abs/1902.08437

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