A bstract We consider two nonlinear sigma models on de Sitter background which involve the same derivative interactions as quantum gravity but without the gauge issue. The first model contains only a single field, which can be reduced to a free theory by a local field redefinition; the second contains two fields and cannot be so reduced. Loop corrections in both models produce large temporal and spatial logarithms which cause perturbation theory to break down at late times and large distances. Many of these logarithms derive from the “tail” part of the propagator and can be summed using a variant of Starobinsky’s stochastic formalism involving a curvaturedependent effective potential. The remaining logarithms derive from the ultraviolet and can be summed using a variant of the renormalization group based on a special class of curvaturedependent renormalizations. Explicit results are derived at 1loop and 2loop orders.
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Interacting fractons in 2+1dimensional quantum field theory
A bstract We analyze, in perturbation theory, a theory of weakly interacting fractons and nonrelativistic fermions in a 2+1 dimensional Quantum Field Theory. In particular we compute the 1loop corrections to the self energies and interaction vertex, and calculate the associated 1loop Renormalization Group flows of the coupling constants. Surprisingly, we find that the fractonfermion coupling does not flow due to an emergent coordinatedependent symmetry of the effective Lagrangian, making this model a welldefined quantum field theory. We provide additional discussions on the regularization and renormalization of interacting fractonic theories, as well as both qualitative and quantitative remarks regarding the theory at finite temperature and finite chemical potential.
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 Award ID(s):
 1914679
 NSFPAR ID:
 10337803
 Date Published:
 Journal Name:
 Journal of High Energy Physics
 Volume:
 2022
 Issue:
 3
 ISSN:
 10298479
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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