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arXiv · 1801.08171

Euclidean scalar field theory in the bi-local approximation

S. Nagy·J. Polonyi·I. Steib
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Abstract

The blocking step of the renormalization group method is usually carried out by restricting it to fluctuations and to local blocked action. The tree-level, bi-local saddle point contribution to the blocking, defined by the infinitesimal decrease of the sharp cutoff in momentum space, is followed within the three dimensional Euclidean $\phi^6$ model in this work. The phase structure is changed, new phases and relevant operators are found and certain universality classes are restricted by the bi-local saddle point.

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S. Nagy, J. Polonyi, I. Steib. 2018-01-24. Euclidean scalar field theory in the bi-local approximation. https://doi.org/10.1103/physrevd.97.085002

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