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arXiv · 2501.17632

Hessian-free force-gradient integrators and their application to lattice QCD simulations

Kevin Schäfers·Jacob Finkenrath·Michael Günther·Francesco Knechtli
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Abstract

We present initial results on Hessian-free force-gradient integrators for lattice field theories. Integrators of this framework promise to provide substantial performance enhancements, particularly for larger lattice volumes where higher-order integrators demonstrate greater efficiency. Numerical results demonstrate the superior efficiency of the proposed integrators compared to commonly employed non-gradient schemes, particularly due to enhanced stability properties. It is anticipated that the advantages of the Hessian-free framework will become even more pronounced in nested integration approaches and for smaller fermion masses, where the numerical stability properties of the integrators become increasingly important.

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Kevin Schäfers, Jacob Finkenrath, Michael Günther, Francesco Knechtli. 2025-01-29. Hessian-free force-gradient integrators and their application to lattice QCD simulations. https://arxiv.org/abs/2501.17632

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