# Fab Four self-interaction in quantum regime

Quantum behavior of the John Lagrangian from the Fab Four class of Covariant Galileons is stud- ied. We consider one-loop corrections to the John interaction due to cubic scalar field interactions. Counter Terms are calculated, one of them belongs to the Fab Four class, the other one to Covariant Galileons. The role of quantum corrections in context of cosmological applications is discussed.

**Comments:**7 pages, 5 figures

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