title: Cosmological classicalization: maintaining unitarity under relevant deformations of the Einstein-Hilbert action.
abstract: Generic relevant deformations of Einstein's gravity theory contain additional degrees of freedom that have a multifaceted stabilization dynamics on curved spacetimes. We show that these relevant degrees of freedom are self-protected against unitarity violations by the formation of classical field lumps that eventually merge to a new background geometry. The transition is heralded by the massive decay of the original vacuum and evolves through a strong coupling regime. This process fits in the recently proposed classicalization mechanism and extends it further to free field dynamics on curved backgrounds.
authors.affiliation: Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universität, Theresienstraße 37, 80333 Munich, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Berkhahn
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Dietrich
authors.forename: Stefan
authors.initials: S
authors.lastname: Hofmann