ABSTRACT
A position in space cannot be assigned but with a limited degree of precision, and only through the intermediary of a material point. David Delphenich concluded that the square root of density becomes ‘more fundamental than the density itself’. The deformation is, in general, not an usual diffeomorphism, even in the classical case when, as a rule, it is modeled by a diffeomorphism. Attaching a reference frame is, according to Élie Cartan, a matter of gauging in the acceptance of Nicholas Georgescu-Roegen for defining the ‘finite’: ‘define once and for all the frame attached to a particular point’. The matter of Earth’s nucleus, or even more generally, of a spatially extended particle, is characterized by the torsion vector. The Fresnel volume is inherently connected to the torsion of the space containing the matter within which the signal is propagating. The existence of this very volume is therefore a necessary physical condition for the possibility of describing the propagation.
