Gravitational Waves from Cosmological Inflation

The recent first direct detection of gravitational waves at LIGO, together with forthcoming experiments aimed to detect gravitational modes produced during inflation, are opening a new exciting era for gravitational wave astronomy. In this PhD project, the student will investigate the dynamics of gravitational waves produced during an early period of cosmological inflation.
In the first part of the project, the student will develop and study new inflationary scenarios, motivated by symmetry principles, which can produce a background of primordial gravitational waves with distinctive features. For example, a large amplitude, or a specific scale dependence, for the n-point functions associated with the tensorial gravitational modes.
In the second part of the project, the student will phenomenologically investigate possible ways to test the theoretical scenarios (s)he developed, using two complementary approaches. In the first approach, the student will analyse their consequences for the statistics of B-modes of the CMB, and the distribution of Large Scale Structure of the Universe. In the second approach, the student will study under which circumstances the primordial gravity wave signal can be detected by current (LIGO) and future (e.g. eLISA) interferometers. Moreover, (s)he will analyse its distinctive properties which will allow observers to distinguish inflationary gravity waves from other sources of gravitational radiation.
The project will cover both theoretical and phenomenological aspects, and will provide the student with a solid broad knowledge on theoretical cosmology, plus a specific, timely expertise on the dynamics of gravity waves in early universe cosmology.