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arXiv · 2210.03834

Improved coarse-graining methods on two dimensional tensor networks including fermions

Muhammad Asaduzzaman·Simon Catterall·Yannick Meurice·Ryo Sakai·Goksu Can Toga
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Abstract

We show how to apply renormalization group algorithms incorporating entanglement filtering methods and a loop optimization to a tensor network which includes Grassmann variables which represent fermions in an underlying lattice field theory. As a numerical test a variety of quantities are calculated for two dimensional Wilson--Majorana fermions and for the two flavor Gross--Neveu model. The improved algorithms show much better accuracy for quantities such as the free energy and the determination of Fisher's zeros.

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Muhammad Asaduzzaman, Simon Catterall, Yannick Meurice, Ryo Sakai, Goksu Can Toga. 2022-10-07. Improved coarse-graining methods on two dimensional tensor networks including fermions. https://doi.org/10.1007/jhep01(2023)024

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