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arXiv · 1704.04458

Two-Loop Corrections to Large Order Behavior of $φ^4$ Theory

Enrico M. Malatesta·Giorgio Parisi·Tommaso Rizzo
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Abstract

We consider the large order behavior of the perturbative expansion of the scalar $φ^4$ field theory in terms of a perturbative expansion around an instanton solution. We have computed the series of the free energy up to two-loop order in two and three dimension. Topologically there is only an additional Feynman diagram with respect to the previously known one dimensional case, but a careful treatment of renormalization is needed. The propagator and Feynman diagrams were expressed in a form suitable for numerical evaluation. We then obtained explicit expressions summing over $O(10^3)$ distinct eigenvalues determined numerically with the corresponding eigenfunctions.

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Enrico M. Malatesta, Giorgio Parisi, Tommaso Rizzo. 2018-05-16. Two-Loop Corrections to Large Order Behavior of $φ^4$ Theory. https://doi.org/10.1016/j.nuclphysb.2017.07.011

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