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arXiv · 2007.06323

First-principle simulations of 1+1d quantum field theories at $\theta=\pi$ and spin-chains

Tin Sulejmanpasic·Daniel Daniel Göschl·Christof Gattringer
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Abstract

We present a lattice study of a 2-flavor $U(1)$ gauge-Higgs model quantum field theory with a topological term at $\theta=\pi$. Such studies are prohibitively costly in the standard lattice formulation due to the sign-problem. Using a novel discretization of the model, along with an exact lattice dualization, we overcome the sign-problem and reliably simulate such systems. Our work provides the first ab initio demonstration that the model is in the spin-chain universality class, and demonstrates the power of the new approach to $U(1)$ gauge theories.

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Tin Sulejmanpasic, Daniel Daniel Göschl, Christof Gattringer. 2020-07-13. First-principle simulations of 1+1d quantum field theories at $\theta=\pi$ and spin-chains. https://doi.org/10.1103/physrevlett.125.201602

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