75 citations · 212 across the 13 of their papers we have counts for
13 papers
A novel definition of real Fourier transform
Fulvio Sbisà
We propose a novel definition of Fourier transform, with the property that the transform of a real function is again a real function (without doubling the number of real components…
The divergence of Van Hove's model and its consequences
Fulvio Sbisà
We study a regularized version of Van Hove's 1952 model, in which a quantum field interacts linearly with sources of finite width lying at fixed positions. We show that the central…
On Léon van Hove's 1952 article on the foundations of Quantum Field Theory
Fulvio Sbisà
In 1952, Léon van Hove published an article, in French, with the title ``Les difficultés de divergences pour um modèle particulier de champ quantifié''. The article is frequently c…
Neutron star masses in -gravity
Fulvio Sbisà, Pedro O. Baqui, Tays Miranda +2
We address the issue of the existence of inequivalent definitions of gravitational mass in -gravity. We present several definitions of gravitational mass, and discuss the fo…
Degravitation and the Cascading DGP Model
Fulvio Sbisà
We consider the 6D Cascading DGP model, a braneworld model which is a promising candidate to realize the phenomenon of the degravitation of vacuum energy. Focusing on a recently pr…
Pressure effects in the weak-field limit of f(R) = R + alpha R^2 gravity
Fulvio Sbisà, Oliver F. Piattella, Sergio E. Jorás
We investigate the linear regime of f(R) = R + alpha R^2 gravity for static, spherically symmetric and asymptotically flat configurations of matter. We show that, in vacuum and dee…
Thin limit of the 6D Cascading DGP model
Fulvio Sbisà
A thin limit description of the 6D Cascading DGP model is derived, starting from a configuration where both the codimension-1 and the codimension-2 branes are thick. Postulating th…
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…
Characterising Vainshtein Solutions in Massive Gravity
Fulvio Sbisà, Gustavo Niz, Kazuya Koyama +1
We study static, spherically symmetric solutions in a recently proposed ghost-free model of non-linear massive gravity. We focus on a branch of solutions where the helicity-0 mode…