The Einstein-Hilbert action is the simplest possible generally covariant action for gravity. While Einstein's equations conform with all observational data, theoretical considerations suggest the possibility to add higher curvature correction terms to Einstein's theory.
The prospect of a stochastic gravitational wave (GW) background from the primordial universe offers a promising new window for cosmology and fundamental physics.
Visakan Balakumar, Marie Curie seconded fellow within the RISE FunFiCO project, coordinated by Gr@v, authored a YouTube outreach video on superradiance. Check it out here!
The Domain Wall (DW) problem is the fact that DW networks that result from the spontaneous breaking of discrete symmetries tend to dominate the universe's energy budget.
However, if the symmetry is not exact the network annihilates and the problem turns into a virtue, as the network tends to be an abundant component before its collapse, and is thus easier to probe.
Our group coordinated the "Numerical Relativity and High Energy Physics" IRSES network (2012-2015). Here is a list of the global network meetings organized:
