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R-symmetry in the Q-exact (2,2) 2d lattice Wess-Zumino model

Joel Giedt
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Abstract

In this article we explore the R-symmetry of the (2,2) 2d Wess-Zumino model. We study whether or not this symmetry is approximately realized in the Q-exact lattice version of this theory. Our study is nonperturbative: it relies on Monte Carlo simulations with dynamical fermions. Irrelevant operators in the lattice action explicitly break the R-symmetry. In spite of this, it is found to be a symmetry of the effective potential. We find nonperturbative evidence that the nonrenormalization theorem of the continuum theory is recovered in the continuum limit; e.g., there is no additive mass renormalization. In our simulations we find that Fourier acceleration of the hybrid Monte Carlo algorithm allows us to avoid difficulties with critical slowing-down.

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Joel Giedt. 2005-07-14. R-symmetry in the Q-exact (2,2) 2d lattice Wess-Zumino model. https://doi.org/10.1016/j.nuclphysb.2005.08.004

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