Abstract
We study the chiral limit of 2d QCD with a single quark flavor at finite Nc using LCT. By modifying the LCT basis according to the quark mass in a manner motivated by ’t Hooft’s analysis, we are able to restore convergence for quark masses much smaller than the QCD strong coupling scale. For such small quark masses, the IR of the theory is expected to be well described by the Sine-Gordon model. We verify that LCT numerics are able to capture in detail the spectrum and correlation functions of the Sine-Gordon model. This opens up the possibility for studying deformations of various integrable CFTs using LCT by considering the chiral limit of QCD like theories.
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Acknowledgments
We thank Zuhair Khandker, Silviu Pufu, Matthew Walters, and Xi Yin for helpful conversations, and Matthew Walters for collaboration at an early stage of the project; we also thank Igor Klebanov and Matthew Walters for comments on an earlier draft. ALF and EK were supported in part by the US Department of Energy Office of Science under Award Number DE-SC0015845, NA, ALF and EK were supported in part by the Simons Collaboration Grant on the Non-Perturbative Bootstrap, and ALF in part by a Sloan Foundation fellowship. YX was supported by a Yale Mossman Prize Fellowship in Physics.
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Anand, N., Fitzpatrick, A.L., Katz, E. et al. Chiral limit of 2d QCD revisited with lightcone conformal truncation. J. High Energ. Phys. 2024, 189 (2024). https://doi.org/10.1007/JHEP01(2024)189
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DOI: https://doi.org/10.1007/JHEP01(2024)189