The Friedmann equations valid for the transparent universe are modified for
the universe with opacity caused by absorption of light by ambient cosmic dust
in intergalactic space. The modified equations lead to a cosmological model, in
which cosmic opacity produces radiation pressure that counterbalances
gravitational forces. The proposed model predicts a cyclic
expansion/contraction evolution of the Universe within a limited range of scale
factors with no initial singularity. The maximum redshift, at which the
contraction of the Universe stops, is ~14-15. The model avoids dark energy and
removes some other tensions of the standard cosmological model.Comment: 10 pages, 3 figures. arXiv admin note: substantial text overlap with
arXiv:1902.1052