Quantum effective actions from nonperturbative worldline dynamics

  title={Quantum effective actions from nonperturbative worldline dynamics},
  author={Holger Gies and J. S'anchez--Guill'en and Ricardo V'azquez},
  journal={Journal of High Energy Physics},
We demonstrate the feasibility of a nonperturbative analysis of quantum field theory in the worldline formalism with the help of an efficient numerical algorithm. In particular, we compute the effective action for a super-renormalizable field theory with cubic scalar interaction in four dimensions in quenched approximation (small- Nf expansion) to all orders in the coupling. We observe that nonperturbative effects exert a strong influence on the infrared behavior, rendering the massless limit… 

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