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arXiv · 2312.13929

Approaching the conformal WZW behavior in the infrared limit of two-dimensional massless QCD: a lattice study

Nikhil Karthik·Rajamani Narayanan·Sruthi A. Narayanan
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Abstract

Two-dimensional QCD with $N_c$ colors and $N_f$ flavors of massless fermions in the fundamental representation is expected to exhibit conformal behavior in the infrared governed by a $u(N_f)$ WZW model with level $N_c$. Using numerical analysis within the lattice formalism with exactly massless overlap fermions, we show the emergence of such behavior in the infrared limit. Both the continuum extrapolated low-lying eigenvalues of the massless Dirac operator and the propagator of scalar mesons exhibit a flow from the ultraviolet to the infrared. We find that the amplitude of the conserved current correlator remains invariant under the flow, while the amplitude of the scalar correlator approaches $N_f$-independent values in the infrared.

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Nikhil Karthik, Rajamani Narayanan, Sruthi A. Narayanan. 2023-12-21. Approaching the conformal WZW behavior in the infrared limit of two-dimensional massless QCD: a lattice study. https://arxiv.org/abs/2312.13929

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