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arXiv · 1305.3322

A Hierarchical Finite Element Method for Quantum Field Theory

Arnab Kar·Fred Moolekamp·S. G. Rajeev
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Abstract

We study a model of scalar quantum field theory in which space-time is a discrete set of points obtained by repeatedly subdividing a triangle into three triangles at the centroid. By integrating out the field variable at the centroid we get a renormalized action on the original triangle. The exact renormalization map between the angles of the triangles is obtained as well. A fixed point of this map happens to be the cotangent formula of Finite Element Method which approximates the Laplacian in two dimensions.

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Arnab Kar, Fred Moolekamp, S. G. Rajeev. 2013-05-21. A Hierarchical Finite Element Method for Quantum Field Theory. https://doi.org/10.1142/s0217732313501393

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