AUSL Medical Physics
Laboratory; Via Enrico Fermi 15, 01100 Viterbo (Italy) and Einstein-Galilei
Institute for Theoretical Physics and Advanced Mathematics (I.F.M.); Via
Santa Gonda 14, 59100 Prato Italy.
Dark matter clustered in galaxies or clusters is usually interpreted as a new type of material substance subject
only to gravitational force. Alternative explanations envisage deviations of the laws of gravity, of the equations of motion
or of both from their commonly accepted form. The additional possibility is explored here that the true origin of the
effects depicted as “dark matter” should be seen in connection with local violations of the inertia principle, resulting from
the quantized granular structure of the cosmic inertial field. Within the framework of Fantappié-Arcidiacono Projective
General Relativity (PGR), this quantization appears to be the dual of that of elementary particle masses, which has been
suggested for a long time. This hypothesis does not appear to contradict known facts relating to galaxy rotation and to
gravitational lensing of clusters. Furthermore, it introduces a new timescale for the coupling of space expansion with
structure formation, which could be of interest in cosmology.