Gravitation

The Section Gravitation deals with the latest research and developments, both theoretical and experimental, in the field of gravitational physics.

Among the four fundamental interactions known to date, gravitation is the one that humankind has been aware of for the longest time and, at the same time, the least precisely known due to its extreme weakness compared with the others. Gravitation shapes the fabric of our universe uncontested at the largest scales where its current best description, general relativity, may be challenged by the phenomenology connected with the cosmic accelerated expansion. At the same time, gravitation is called to a difficult, and still uncelebrated, marriage with quantum mechanics at the smallest ones where general relativity should lose its physical meaning. Empirical studies of gravitational interaction have always been difficult because of the feebleness of its effects with respect to the other ones. Dedicated experiments and/or observational campaigns are usually very long and, in many cases, also quite expensive. Nonetheless, the recent direct discovery of gravitational waves with ground-based interferometers and the imaging of the shadow of the supermassive black hole at the center of the giant elliptical galaxy M87 have shed light on phenomena occurring in highly dynamical regimes and strong gravitational fields that, until recently, were precluded from direct observation.

This Section covers the many faces of gravitation in its theoretical and experimental/observational aspects providing researchers worldwide with an up-to-date venue to share their latest results, conjectures, and hypotheses.

The following list includes topics covered in the Section but is by no means exhaustive:

Topics of This Section:

General relativity

Relativistic astrophysics

Black holes and compact objects

Modified models of gravitation

Gravitational waves: data analysis, astrophysical sources, and detectors

Quantum gravity

Experimental tests of gravitational theories