Astrophysical background of gravitational waves: anisotropies, polarization and cross-correlations with cosmological observables. 

 

Slow-roll single-field inflation constitutes the main paradigm of the
Early Universe. But this model suffers from a number of conceptual issues
that naturally lead to the consideration of multifield models of
inflation with curved field space, that have recently been under scrutiny
as realistic realizations of high-energy physics in the Early Universe.
I will show that the non-trivial internal geometry reshuffles
observational predictions from inflation, at the level of the background
(geometrical destabilisation of inflation), of linear

The KATRIN (Karlsruhe Tritium Neutrino) experiment investigates the energetic endpoint of the tritium beta-decay spectrum to determine the effective mass of the electron anti-neutrino. The collaboration reported its first neutrino mass result in fall 2019. Its unprecedented tritium source luminosity and spectroscopic quality make it a unique instrument to also search for physics beyond the standard model such as eV or keV sterile neutrinos.

The idea that low energy fields such as Gravitons or Axions can be 
thought of as composite particles has been entertained since a long 
time. We revisit this idea motivated by the AdS/CFT correspondence. We 
focus in the case of axions and show that hidden sectors coupled to SM 
fields may provide an emergent axionic field that is a composite of the 
hidden fields (instanton density). This is a more general phenomenon 
beyond holographic theories. We study the general properties of such an 
"emergent axion", without a PQ symmetry. The construction goes beyond