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arXiv · 0710.1785

Dynamical overlap fermions with increased topological tunnelling

N. Cundy·S. Krieg·T. Lippert·A Schaefer
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Abstract

We present two improvements to our previous dynamical overlap HMC algorithm. We introduce a new method of differentiating the eigenvectors of the Kernel operator, which removes an instability in the fermionic force. Secondly, by simulating part of the fermion determinant exactly, without pseudo-fermions, we are able to increase the rate of topological tunnelling by a factor of more than ten, reducing the auto-correlation.

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N. Cundy, S. Krieg, T. Lippert, A Schaefer. 2007-10-09. Dynamical overlap fermions with increased topological tunnelling. https://arxiv.org/abs/0710.1785

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