2021-03-19 11:00  1F auditorium

Gravitational Waves and their Tidal Forces in Cosmological Spacetimes

Yen-Wei Liu

The propagation of gravitational waves (GWs), despite being well-studied in the asymptotically-flat spacetimes, has not been much addressed in a cosmological background until very recently. As most of the LIGO/Virgo confirmed events have seen such non-trivial redshifts from their progenitors, it becomes more desirable to investigate these GW signatures from first principles. Among other things, the scalar acoustic waves associated with the scalar portion of the metric have been uncovered to potentially coexist with their usual spin-2 counterparts in a relativistic fluid-driven cosmology. I will discuss these new features in some physical scenarios of cosmological interest.