  The model of the homogenous and isotropic universe is considered in which the
coordinate system of reference is not defined by the matter but is a priori
specified. The scale factor of the universe changes following the linear law.
The scale of mass changes proportional to the scale factor. The temperature of
the relativistic matter changes inversly proportional to the root of the scale
factor. The model under consideration avoids the flatness and horizon problems.
The predictions of the model are fitted to the observational constraints:
Hubble parameter, age of the universe, magnitude-redshift relation of the
high-redshift supernovae, and primordial nucleosynthesis.
