301 citations · 401 across the 8 of their papers we have counts for
6 papers · 1 filter
Microscopic Picture of Non-Relativistic Classicalons
Felix Berkhahn, Sophia Müller, Florian Niedermann +1
A theory of a non-relativistic, complex scalar field with derivatively coupled interaction terms is investigated. This toy model is considered as a prototype of a classicalizing th…
Brane Induced Gravity: From a No-Go to a No-Ghost Theorem
Felix Berkhahn, Stefan Hofmann, Florian Niedermann
Numerous claims in the literature suggest that gravity induced on a higher co-dimensional surface violates unitarity in the weak coupling regime. However, it remained unclear, why…
Island of Stability for Consistent Deformations of Einstein's Gravity
Felix Berkhahn, Dennis Dietrich, Stefan Hofmann +2
We construct explicitly deformations of Einstein's theory of gravity that are consistent and phenomenologically viable since they respect, in particular, cosmological backgrounds.…
Consistency of Relevant Cosmological Deformations on all Scales
Felix Berkhahn, Dennis D. Dietrich, Stefan Hofmann
Using cosmological perturbation theory we show that the most relevant defor- mation of gravity is consistent at the linear level. In particular, we prove the absence of uni- tarity…
Cosmological Classicalization: Maintaining Unitarity under Relevant Deformations of the Einstein-Hilbert Action
Felix Berkhahn, Dennis D. Dietrich, Stefan Hofmann
Generic relevant deformations of Einstein's gravity theory contain additional degrees of freedom that have a multi-facetted stabilization dynamics on curved spacetimes. We show tha…
Self-Protection of Massive Cosmological Gravitons
Felix Berkhahn, Dennis D. Dietrich, Stefan Hofmann
Relevant deformations of gravity present an exciting window of opportunity to probe the rigidity of gravity on cosmological scales. For a single-graviton theory, the leading releva…