The problem of missing mass in the Universe, at the scale of galaxies,
large-scale structures, and its global content, is a multi-faceted
enigma. In the cold dark matter scenario, one of the main candidate for the
non-baryonic particles, is the neutralino, the most stable of the
super-symmetric particles.
However, supersymmetry does not appear as expected in the LHC
experiments at CERN....
The possible existence of particles with negative mass has long been considered, starting from the seminal work of H. Bondi [1]. In a cosmological context, it was shown more recently that negative mass solutions are viable in a de Sitter universe [2]. Negative masses have also been considered in bi- and multi-metric extensions of General Relativity [3].
Besides, one cannot but note the...
A rich program to test the behaviour of antimatter in gravitational fields is ongoing at CERN. The Antiproton Decelerator facility provides a low energy antiproton beam that allows the efficient trapping of antiprotons and successful synthesis of antihydrogen. Antiproton and antihydrogen spectroscopy experiments are now able to investigate annual variations, signature of a gravitational...
The AEgIS experiment is an international collaboration based at CERN aiming at measuring the free fall of antihydrogen in the Earth’s gravitational field. To this end, AEgIS makes use of a charge exchange reaction where a cold antiproton plasma stored in a Pennning trap is exposed to a pulsed cloud of positronium atoms prepared in highly excited Rydberg states. Positronium (the bound state of...
