75 citations · 212 across the 13 of their papers we have counts for
5 papers · 1 filter
Modified gravity, the Cascading DGP model and its critical tension
Fulvio Sbisà
We investigate the presence of instabilities in the Cascading DGP model. We start by discussing the problem of the cosmological late time acceleration, and we introduce the modifie…
Modified Theories of Gravity
Fulvio Sbisà
The recent observational data in cosmology seem to indicate that the universe is currently expanding in an accelerated way. An intriguing interpretation of these data is that they…
Classical and quantum ghosts
Fulvio Sbisà
The aim of these notes is to provide a self-contained review of why it is generically a problem when a solution of a theory possesses ghost fields among the perturbation modes. We…
The critical tension in the Cascading DGP model
Fulvio Sbisà, Kazuya Koyama
We study the behaviour of weak gravitational fields in the 6D Cascading DGP model using a bulk-based approach. To deal with the ambiguity in the thin limit of branes of codimension…
Perturbations of Nested Branes With Induced Gravity
Fulvio Sbisà, Kazuya Koyama
We study the behaviour of weak gravitational fields in models where a 4D brane is embedded inside a 5D brane equipped with induced gravity, which in turn is embedded in a 6D spacet…