Hidden Conformal Symmetry from the Lattice

• Main Authors: LSD Collaboration, Appelquist, T, Brower, R. C, Cushman, K. K, Fleming, G. T, Gasbarro, A, Hasenfratz, A, Ingoldby, J, Jin, X. Y, Neil, E. T, Osborn, J. C, Rebbi, C, Rinaldi, E, Schaich, D, Vranas, P, Weinberg, E, Witzel, O
• Format: Journal Article
• Language: English
• Published: 18-12-2023
• Subjects: Physics - High Energy Physics - Lattice; Physics - High Energy Physics - Phenomenology
• DOI: 10.48550/arxiv.2305.03665

Phys.Rev.D 108 (2023) 9, L091505 We analyze newly expanded and refined data from lattice studies of an SU(3)
gauge theory with eight Dirac fermions in the fundamental representation. We
focus on the light composite states emerging from these studies, consisting of
a set of pseudoscalars and a single light scalar. We first consider the view
that this theory is just outside the conformal window. In this case, the
pseudoscalars arise from spontaneous breaking of chiral symmetry. Identifying
the scalar in this case as an approximate dilaton, we fit the lattice data to a
dilaton effective field theory, finding that it yields a good fit even at
lowest order. For comparison, we then consider the possibility that the theory
is inside the conformal window. The fermion mass provides a deformation,
triggering confinement. We employ simple scaling laws to fit the lattice data,
and find that it is of lesser quality.