Tests of gravity theories with Galactic Center observations

Abstract

An active stage of relativistic astrophysics started in 1963 since in this year, quasars were discovered, Kerr solution has been found and the first Texas Symposium on Relativistic Astrophysics was organized in Dallas. Five years later, in 1967--1968 pulsars were discovered and their model as rotating neutron stars has been proposed, meanwhile J. A. Wheeler claimed that Kerr and Schwarzschild vacuum solutions of Einstein equations provide an efficient approach for astronomical objects with different masses. Wheeler suggested to call these objects black holes. Neutron stars were observed in different spectral band of electromagnetic radiation. In addition, a neutrino signal has been found for SN1987A. Therefore, multi-messenger astronomy demonstrated its efficiency for decades even before observations of the first gravitational radiation sources. However, usually, one has only manifestations of black holes in a weak gravitational field limit and sometimes a model with a black hole could be substituted with an alternative approach which very often looks much less natural, however, it is necessary to find observational evidences to reject such an alternative model. After two observational runs the LIGO-- Virgo collaboration provided a confirmation for an presence of mergers for ten binary black holes and one binary neutron star system where gravitational wave signals were found. In addition, in last years a remarkable progress has been reached in a development of observational facilities to investigate a gravitational potential, for instance, a number of telescopes operating in the Event Horizon Telescope network is increasing and accuracy of a shadow reconstruction near the Galactic Center is improving, meanwhile largest VLT, Keck telescopes with adaptive optics and especially, GRAVITY facilities observe bright IR stars at the Galactic Center with a perfecting accuracy.

18 pages, an invited plenary talk at Fourth International Conference on Particle Physics and Astrophysics (ICPPA-2018); accepted for publication in a special issue of the International Journal of Modern Physics D

References in corpus (9)

• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Primordial Black Holes as Dark Matter
• An Update on Monitoring Stellar Orbits in the Galactic Center
• Testing General Relativity with stellar orbits around the supermassive black hole in our Galactic center
• MASTER optical detection of the first LIGO/Virgo neutron stars merging GW170817
• Test of the Gravitational Redshift with Galileo Satellites in an Eccentric Orbit
• Constraints on $R^n$ gravity from precession of orbits of S2-like stars
• Apoastron Shift Constraints on Dark Matter Distribution at the Galactic Center
• A new direction for dark matter research: intermediate mass compact halo objects

Cited by in corpus (4)

• Harvesting energy driven by Comisso-Asenjo process from Kerr-MOG black holes
• Event horizon silhouette: implications to supermassive black holes M87* and SgrA*
• Shadows near supermassive black holes: from a theoretical concept to GR test
• Unscreening of f(R) gravity near the galactic center black hole: Testability through pericenter shift below S0-2's orbit