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Title: Feynman rules for forced wave turbulence
A bstract It has long been known that weakly nonlinear field theories can have a late-time stationary state that is not the thermal state, but a wave turbulent state with a far-from-equilibrium cascade of energy. We go beyond the existence of the wave turbulent state, studying fluctuations about the wave turbulent state. Specifically, we take a classical field theory with an arbitrary quartic interaction and add dissipation and Gaussian-random forcing. Employing the path integral relation between stochastic classical field theories and quantum field theories, we give a prescription, in terms of Feynman diagrams, for computing correlation functions in this system. We explicitly compute the two-point and four-point functions of the field to next-to-leading order in the coupling. Through an appropriate choice of forcing and dissipation, these correspond to correlation functions in the wave turbulent state. In particular, we derive the kinetic equation to next-to-leading order.  more » « less
Award ID(s):
2209116
PAR ID:
10410553
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of High Energy Physics
Volume:
2023
Issue:
1
ISSN:
1029-8479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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