Analytic continuation of functional renormalization group equations

Stefan Floerchinger

doi:10.1007/jhep05(2012)021

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arXiv · 1112.4374

Analytic continuation of functional renormalization group equations

Stefan Floerchinger

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Abstract

Functional renormalization group equations are analytically continued from imaginary Matsubara frequencies to the real frequency axis. On the example of a scalar field with O(N) symmetry we discuss the analytic structure of the flowing action and show how it is possible to derive and solve flow equations for real-time properties such as propagator residues and particle decay widths. The formalism conserves space-time symmetries such as Lorentz or Galilei invariance and allows for improved, self-consistent approximations in terms of derivative expansions in Minkowski space.

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Stefan Floerchinger. 2011-12-19. Analytic continuation of functional renormalization group equations. https://doi.org/10.1007/jhep05(2012)021

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