TorchSim: An efficient atomistic simulation engine in PyTorch

Orion Cohen; Janosh Riebesell; Rhys Goodall; Adeesh Kolluru; Stefano Falletta; Joseph Krause; Jorge Colindres; Gerbrand Ceder; Abhijeet S. Gangan

arXiv · 2508.06628

TorchSim: An efficient atomistic simulation engine in PyTorch

Orion Cohen·Janosh Riebesell·Rhys Goodall·Adeesh Kolluru·Stefano Falletta·Joseph Krause·Jorge Colindres·Gerbrand Ceder·Abhijeet S. Gangan

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Abstract

We introduce TorchSim, an open-source atomistic simulation engine tailored for the Machine Learned Interatomic Potential (MLIP) era. By rewriting core atomistic simulation primitives in PyTorch, TorchSim can achieve orders of magnitude acceleration for popular MLIPs. Unlike existing molecular dynamics packages, which simulate one system at a time, TorchSim performs batched simulations that efficiently utilize modern GPUs by evolving multiple systems concurrently. TorchSim supports molecular dynamics integrators, structural relaxation optimizers, both machine-learned and classical interatomic potentials (such as Lennard-Jones, Morse, soft-sphere), batching with automatic memory management, differentiable simulation, and integration with popular materials informatics tools.

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Orion Cohen, Janosh Riebesell, Rhys Goodall, Adeesh Kolluru, Stefano Falletta, Joseph Krause, Jorge Colindres, Gerbrand Ceder, Abhijeet S. Gangan. 2025-08-08. TorchSim: An efficient atomistic simulation engine in PyTorch. https://arxiv.org/abs/2508.06628

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