Geodesic structure of the accelerated stephani universe
Authors
BORMOTOVA, Iryna (804 Ukraine, belonging to the institution), Olena KOPTĚVA (804 Ukraine, belonging to the institution) and Zdeněk STUCHLÍK (203 Czech Republic, belonging to the institution)
For the spherically symmetric Stephani cosmological model with an accelerated expansion, we investigate the main scenarios of the test particle and photon motion. We show that a comoving observer sees an appropriate picture. In the case of purely radial motion, the radial velocity decreases slightly with time due to the universe expansion. Both particles and photons spiral out of the center when the radial coordinate is constant. In the case of the motion with arbitrary initial velocity, the observable radial distance to the test particle can increase under negative observable radial velocity.