Gravitation and Cosmology

Energy-scale systems typical for astrophysics and cosmology have long been studied in the semiclassical approach in which General Relativity describes gravity while matter is described by quantum field theories. From here, classical effective descriptions and fully quantum models are developed for:

Gravitational interactions: effective theories of low-energy and modified gravity; quantization by coherent states; quantum field theories on curved space and analogies with condensed state models; ultraviolet completeness and existence of minimum length scales; thermodynamics of scalar-tensor theories.

Theoretical cosmology: models of cosmological inflation and cosmic microwave background radiation; dark energy models, theories of modified gravity and dark matter; quantum cosmology and the study of cosmological singularities, with applications to inflation, reheating, matter, dark radiation and energy, and the production of primordial black holes. 

Physics of black holes and compact astrophysical objects: quantum models and effects for high-compactness self-gravitating systems; gravitational collapse and formation of horizons with Hawking radiation; resolution of classical singularities and regular quantum black holes; exotic astrophysical objects and compact sources in quantum and post-Newtonian gravitation; perturbations and emission of gravitational waves.

Research activities

Quantum field theories of gravity

This line of research aims at investigating gravitational interactions at length and energy scales where quantum effects cannot be neglected. Various approaches are followed, such as: i) Low-energy effective field theories, ii) Ultra-violet completion, renormalization group flow and Asymptotic Safety,  iii) Modified gravity theories, iv) Corpuscular models and ultra-violet self-completion; v) Quantum field theories on curved backgrounds and analogue solid state models; vi) Quantum gravity aspects related with a minimum measurable length and the statistical interpretation of the gravitational field equations.

Theoretical cosmology

The Universe evolution is studied from the early instants of time after the Big Bang; i) models of inflationary cosmology and cosmic microwave background radiation; ii)  Models of dark energy, modified gravity theories and dark matter; iii) Quantum cosmology and the fate of cosmological singularities; iv) String cosmology with application to cosmological inflation, reheating, dark matter radiation and energy; v) Primordial black hole production.

Physics of black holes and compact astrophysical objects

Gravitational interactions are investigated for physical systems in extreme configurations like black holes. In particular, we consider: i) Analogue models for the Hawking radiation; ii) Horizon formation and onset of Hawking radiation in the gravitational collapse of compact objects, the possible removal of classical singularities and regular black holes; iii) Minimal Geometric Deformation for exotic compact astrophysical objects and compact sources in post-Newtonian quantum gravity.

National and international projects and collaborations

Our research activities are also supported by the INFN initiatives: FLAG, ST&FI,  QUAGRAP.

At the international level, we mention University of Sussex, UK (X. Calmet), University of Opava, CZ, ABC Federal, BR, LMU, D, ISS, RO, Bishop U., CA, Landau Institute, Moscow, Lebedev Institute, Moscow,  JINR, Dubna, University of Lomonosov, University of Colonia.