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arXiv · 1912.04425

Renormalization of a Contact Interaction on a Lattice

Christopher Körber·Evan Berkowitz·Thomas Luu
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Abstract

Contact interactions can be used to describe a system of particles at unitarity, contribute to the leading part of nuclear interactions and are numerically non-trivial because they require a proper regularization and renormalization scheme. We explain how to tune the coefficient of a contact interaction between non-relativistic particles on a discretized space in 1, 2, and 3 spatial dimensions such that we can remove all discretization artifacts. By taking advantage of a latticized L\"uscher zeta function, we can achieve a momentum-independent scattering amplitude at any finite lattice spacing.

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Christopher Körber, Evan Berkowitz, Thomas Luu. 2019-12-10. Renormalization of a Contact Interaction on a Lattice. https://arxiv.org/abs/1912.04425

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