Assuming that a particle and its antiparticle have the gravitational charge
of the opposite sign, the physical vacuum may be considered as a fluid of
virtual gravitational dipoles. Following this hypothesis, we present the first
indications that dark matter may not exist and that the phenomena for which it
was invoked might be explained by the gravitational polarization of the quantum
vacuum by the known baryonic matter.Comment: We have added an Appendix in order to show that the gravitational
polarization of the quantum vacuum allows the understanding of the
universality of the central surface density of galaxy dark matter haloes, the
cored dark matter haloes in dwarf spheroidal galaxies, the non-existence of
dark disks in spiral galaxies and distribution of dark matter after collision
of clusters of galaxie
