  In the standard cosmological theory one uses the Einstein concepts of space
and time as were originally introduced for the special theory of relativity and
the general relativity theory. According to this approach all physical
quantities are described in terms of the continuum spatial coordinates and
time. Using general relativity theory a great progress has been made in
understanding the evolution of the Universe. Cosmologists usually measure
spatial distances and redshifts of faraway galaxies as expressed by the Hubble
expansion. In recent years this fact was undertaken to develop new theories in
terms of distances and velocities (redshift). While in Einstein's relativity
the propagation of light plays the major role, in the new theory it is the
expansion of the Universe that takes that role and appears at the outset. The
cosmic time becomes crucial in these recent theories, which in the standard
theory is considered to be absolute but here it is relative. In this lecture
this new approach to cosmology is presented.
