Whereas repulsive gravity was considered as a fringe concept until the
mid-1990's, the growingexperimental evidence since this epoch for repulsive
gravity, in what is now called Dark Energy,for lack of a better understanding
of its nature, has led to a vast literature in order to attemptto characterize
this repulsive component, and notably its equation of state. In the following,
Iwill show that we can use cosmology to test the hypothesis that antimatter is
at the origin ofrepulsive gravity, may play the role of a Dark Energy component
and, more surprisingly, maymimic the presence of Dark Matter, and justify the
MOND phenomenology. More directly,three experiments, AEgIS, ALPHA-g and Gbar,
are attempting to measure the action ofgravitation on cold atoms of
antihydrogen at CERN in a near future. Finally, I note thatCP violation might
be explained by antigravity and I briefly recall the motivations for
thisassertion.Comment: 33rd Rencontres de Blois: Exploring the Dark Universe, May 2022,
Blois, Franc