Research units

Gravitation and Cosmology Research Group

Simulation of transition and effects of a point-like gravitational microlens on the radiation from a relativistic accretion disk around a supermassive black hole.

Comparison between the simulated Keplerian orbit of the S2 star (red dashed line) and its orbit in modified Rn gravity (blue solid line) around the central supermassive black hole Sgr A* of the Milky Way during 75 orbital periods.

The Gravitation and Cosmology Research Group conducts the investigations of the gravitation and related astronomical and cosmological phenomena and objects. These investigations include theoretical considerations, numerical simulations and comparisons of the obtained results with astronomical observations, and their main scientific goal is to obtain new fundamental knowledge about the gravitational interaction and its effects on different astrophysical scales, from the Solar System, through galactic, extragalactic to cosmological scales.

Research topics of the Gravitation and Cosmology Research Group:

  • Single and binary black holes in the centers of galaxies and quasars, as well as their relativistic effects (e.g. orbital precession and gravitational redshift)
  • Gravitational waves (from massive binary systems and primordial ones) and the corresponding electromagnetic effects of their sources
  • Gravitational lenses and their application in observational cosmology and for studying the distribution of visible and dark matter in source and lens galaxies
  • Testing the predictions of the standard (General Relativity) and modified gravity theories using astronomical observations
  • Standard ΛCDM, as well as cosmological models based on alternative theories of gravity and their ability to explain the Hubble tension
  • Explaining the observed galactic and extragalactic dynamics (the baryonic Tully-Fisher relation of spiral galaxies and the fundamental plane of elliptical galaxies), as well as the observed anomalies in the motion of the Solar System planets without the dark matter hypothesis
  • Extreme accreting quasars as distance indicators in cosmology
  • Variability of active galaxies and quasars through spectroscopic monitorings (time series analysis with simultaneous line and SED modeling of quasar monitoring spectra)
  • Nonlinear density wave theory in galactic dynamics explaining flat rotation curves
  • Ultra high energy cosmic rays acceleration in plasma wave turbulence

Members of the Gravitation and Cosmology Research Group:

  • Predrag Jovanović (PI), Full Research Professor
  • Nataša Bon, Associate Research Professor
  • Edi Bon, Associate Research Professor
  • Miroslava Vukčević, Assistant Research Professor