Matching high-energy electroweak fermion loops onto the Fermi theory without higher dimensional operators

Roberto Pittau

doi:10.1016/j.nuclphysb.2019.114835

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arXiv · 1902.01767

Matching high-energy electroweak fermion loops onto the Fermi theory without higher dimensional operators

Roberto Pittau

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Abstract

We derive the conditions for matching high-energy renormalizable Quantum Field Theories onto low-energy nonrenormalizable ones by means of the FDR approach described in Fortsch.Phys. 63 (2015) 132-141. Our procedure works order-by-order in the loop expansion and avoids the addition of higher dimensional interactions into the nonrenormalizable Lagrangian. To illustrate our strategy, we match the high-energy fermion-loop corrections computed in the complete electroweak theory onto the nonrenormalizable four-fermion Fermi model. As a result, the Fermi Lagrangian can be used without modifications to reproduce, at arbitrary loop orders and energies, the exact electroweak interactions between two massless fermion lines induced by one-fermion-loop resummed gauge boson propagators.

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Roberto Pittau. 2019-02-05. Matching high-energy electroweak fermion loops onto the Fermi theory without higher dimensional operators. https://doi.org/10.1016/j.nuclphysb.2019.114835

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