The decade of Gravitational Waves and space-based detector eLISA
100 years ago, Einstein predicted the existence of Gravitational Waves (GW) as a consequence of his theory of General Relativity. Today we have confirmed the Einstein predictions with the recent detection of GW150914 by the advanced LIGO (aLIGO) detector. This ground based detector will be joined in the next years by the space detectors “eLISA”, that will survey the low-frequency gravitational-wave sky (from 0.1 mHz to 1 Hz), a frequency band inaccessible from the Earth. The eLISA interferometer, in addiction to detection and characterization of GW of astrophysical origin (such that coming from coalescences of massive black holes and from the inspirals of stellar-mass black holes), as we will see, will also give strong information about other possible sources of GW in the early universe, like particle production during inflation, phase transitions, etc.
In this talk I will briefly review the physics of gravitational waves and gravitational-wave detector like eLISA, and then I will mainly discuss on the promise of these measurements for giving informations about the physics of the early universe.