Most of the elementary particles discovered in the past century have Compton wavelengths that are much smaller than the size of the atom, and, therefore, they cannot mediate any long-range forces between atoms. This changes in the early Universe, when the horizon size is small. The forces that mediate attractive interactions between particles, such as Yukawa forces, are of particular interest...
We show that primordial black holes $-$ in the observationally allowed mass window with $f_{\rm pbh}=1$ $-$ formed from late nucleating patches in a first order phase transition imply upcoming gravitational wave interferometers will see a large stochastic background arising from the bubble collisions. As an example, we use a classically scale invariant $B-L$ model, in which the right handed...
We used H.E.S.S. gamma-ray observations of Sgr A to derive novel limits on the Dark Matter (DM) annihilation cross-section. I will discuss their dependence on uncertainties i) in the DM halo profile, which we varied from peaked to cored, and ii) in the shape of the DM spike around Sgr A dynamically heated by the nuclear star cluster. For peaked halo profiles and depending on the heating of...
Cosmological simulations of Milky-Way like galaxies
