Within the framework of ΛCDM, the local determination of the Hubble constant disagrees -- at the 4.4 sigma level -- with that inferred from the very accurate CMB observations by the Planck satellite. This clearly motivates the study of extensions of the standard cosmological model that could reduce such tension. Proposed extensions of ΛCDM that reduce this so-called Hubble tension require an...
The central measured Standard Model parameters indicate that, at large scale, the Higgs potential develops a second minimum at energy lower than the current Electroweak vacuum.
This has important consequence for cosmology. For instance, the dynamics of the Higgs during inflation could have triggered the decay of the EW vacuum with fatal consequences for our Universe. By requiring that this...
The stochastic gravitational-wave background (SGWB) is formed from the incoherent superposition of many GW sources throughout cosmic history. I will briefly summarise the astrophysical and cosmological sources that contribute to the SGWB and the ongoing searches by cross-correlating data between multiple GW detectors. I will review the current limits on the SGWB and the consequences for...
The observation of Gravitational Waves (GWs) has opened up a whole new avenue for constraining and detecting particle Dark Matter (DM). One of the most promising systems to study is the Intermediate Mass Ratio Inspiral (IMRI): a stellar-mass compact object such as a black hole or neutron star inspiraling towards an intermediate mass black hole, thousands of times more massive than the Sun....
Ultra light axion fuzzy dark matter (FDM) has recently risen as a topical alternative that solves some of the galactic scale problems associated CDM-based structure formation. The long de Broglie wavelength leads for example to constant density cores replacing the density cups at the centres of CDM haloes.
This same property however also leads to interference patterns and accompanying...
