English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In order to explore some general features of modified theories of gravitywhich involve higher derivatives and spontaneous Lorentz and/or diffeomorphismsymmetry breaking, we study the recently proposed new version of covariantrenormalizable gravity (CRG). CRG attains power-counting renormalizability viahigher derivatives and introduction of a constrained scalar field andspontaneous symmetry breaking. We obtain an Arnowitt-Deser-Misnerrepresentation of the CRG action in four-dimensional spacetime with respect toa foliation of spacetime adapted to the constrained scalar field. The resultingaction is analyzed by using Hamiltonian formalism. We discover that CRGcontains two extra degrees of freedom. One of them carries negative energy (aghost) and it will destabilize the theory due to its interactions. This resultis in contrast with the original paper [Phys. Lett. B 701, 117 (2011),arXiv:1104.4286 [hep-th]], where it was concluded that the theory is free ofghosts and renormalizable when we analyze fluctuations on the flat background.

Higher derivative gravity with spontaneous symmetry breaking: Hamiltonian analysis of new covariant renormalizable gravity