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Published on: November 15, 2013
Cosmological classicalization: maintaining unitarity under relevant deformations of the Einstein-Hilbert action
Felix Berkhahn1, Dennis D Dietrich, Stefan Hofmann
1Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universität, Theresienstraße 37, 80333 Munich, Germany.
Physical Review Letters
|June 15, 2011
Summary
Relevant deformations of Einstein
Area of Science:
- Theoretical physics
- Quantum gravity
Background:
- Generic deformations of Einstein's gravity theory introduce extra degrees of freedom.
- These degrees of freedom exhibit complex stabilization dynamics on curved spacetimes.
Purpose of the Study:
- To investigate the stabilization mechanisms of additional degrees of freedom in modified gravity theories.
- To demonstrate how these degrees of freedom avoid unitarity violations through classical field lump formation.
Main Methods:
- Analysis of classical field dynamics on curved spacetimes.
- Investigation of vacuum decay and strong coupling regimes.
- Extension of the classicalization mechanism to free field dynamics.
Main Results:
- Additional degrees of freedom are protected from unitarity violations by forming classical field lumps.
- These lumps merge into a new background geometry, signifying a transition.
- The process involves massive vacuum decay and a strong coupling phase.
Conclusions:
- The classicalization mechanism naturally explains the behavior of these degrees of freedom.
- This study extends classicalization to free field dynamics in curved spacetimes.
- Modified gravity theories can exhibit self-protecting dynamics against unitarity violations.
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