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Bootstrapping pions at large N
A bstract We revisit from a modern bootstrap perspective the longstanding problem of solving QCD in the large N limit. We derive universal bounds on the effective field theory of massless pions by imposing the full set of positivity constraints that follow from 2 → 2 scattering. Some features of our exclusion plots have intriguing connections with hadronic phenomenology. The exclusion boundary exhibits a sharp kink, raising the tantalizing scenario that large N QCD may sit at this kink. We critically examine this possibility, developing in the process a partial analytic understanding of the geometry of the bounds.
Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10376822
Journal Name:
Journal of High Energy Physics
Volume:
2022
Issue:
8
ISSN:
1029-8479
National Science Foundation
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