7 citations · 23 across the 4 of their papers we have counts for
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Soft symmetry improvement of two particle irreducible effective actions
Michael J. Brown, Ian B. Whittingham
Two particle irreducible effective actions (2PIEAs) are valuable non-perturbative techniques in quantum field theory; however, finite truncations of them violate the Ward identitie…
Linear Response Theory for Symmetry Improved Two Particle Irreducible Effective Actions
Michael J. Brown, Ian B. Whittingham, Daniel S. Kosov
We investigate the linear response of an O(N) scalar quantum field theory subject to external perturbations using the symmetry improved two particle irreducible effective action fo…
Symmetry improvement of 3PI effective actions for O(N) scalar field theory
Michael J. Brown, Ian B. Whittingham
[Abridged] n-Particle Irreducible Effective Actions (PIEA) are a powerful tool for extracting non-perturbative and non-equilibrium physics from quantum field theories. Unfortuna…
Two-particle irreducible effective actions versus resummation: analytic properties and self-consistency
Michael Brown, Ian Whittingham
Approximations based on two-particle irreducible (2PI) effective actions (also known as -derivable, Cornwall-Jackiw-Tomboulis or Luttinger-Ward functionals depending on context)…