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arXiv · 2508.19412

A deep first-order system least squares method for the obstacle problem

Gabriel Acosta·Eugenia Belén·Francisco M. Bersetche·Juan Pablo Borthagaray
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Abstract

We propose a deep learning approach to the obstacle problem inspired by the first-order system least-squares (FOSLS) framework. This method reformulates the problem as a convex minimization task; by simultaneously approximating the solution, gradient, and Lagrange multiplier, our approach provides a flexible, mesh-free alternative that scales efficiently to high-dimensional settings. Key theoretical contributions include the coercivity and local Lipschitz continuity of the proposed least-squares functional, along with convergence guarantees via $\Gamma$-convergence theory under mild regularity assumptions. Numerical experiments in dimensions up to 20 demonstrate the method's robustness and scalability, even on non-Lipschitz domains.

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Gabriel Acosta, Eugenia Belén, Francisco M. Bersetche, Juan Pablo Borthagaray. 2025-08-26. A deep first-order system least squares method for the obstacle problem. https://arxiv.org/abs/2508.19412

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