Sgr A*: The Optimal Testbed of Strong-Field Gravity

Abstract

The black hole in the center of the Milky Way has been observed and modeled intensely during the last decades. It is also the prime target of a number of new experiments that aim to zoom into the vicinity of its horizon and reveal the inner working of its spacetime. In this review we discuss our current understanding of the gravitational field of Sgr A* and the prospects of testing the Kerr nature of its spacetime via imaging, astrometric, and timing observations.

11 pages, 11 figures, Invited Talk in Recent Developments in Gravity XIV, June 2010

References in corpus (12)

• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• Testing the No-Hair Theorem with Observations in the Electromagnetic Spectrum: II. Black-Hole Images
• Dynamical Chern-Simons Modified Gravity I: Spinning Black Holes in the Slow-Rotation Approximation
• Testing the general relativistic ''no-hair'' theorems using the galactic center black hole SgrA*
• Observable Properties of Orbits in Exact Bumpy Spacetimes
• Kerr Black Holes are Not Unique to General Relativity
• Testing the No-Hair Theorem with Observations in the Electromagnetic Spectrum. III. Quasi-Periodic Variability
• Perturbed Kerr Black Holes can probe deviations from General Relativity
• Is there a Supermassive Black Hole at the Center of the Milky Way?
• Observing a Black Hole Event Horizon: (Sub)Millimeter VLBI of Sgr A*
• Multipole moments of bumpy black holes
• Gravitational Waves Notes, Issue #2 : "A probe of spacetime and astrophysics: EMRIs"

Cited by in corpus (30)

• Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A${}^{\ast }$
• First Sagittarius A* Event Horizon Telescope Results. VI: Testing the Black Hole Metric
• A Metric for Rapidly Spinning Black Holes Suitable for Strong-Field Tests of the No-Hair Theorem
• Regular Black Hole Metric with Three Constants of Motion
• Testing General Relativity with the Shadow Size of Sgr A*
• A Quantitative Test of the No-Hair Theorem with Sgr A* using stars, pulsars, and the Event Horizon Telescope
• Testing General Relativity with the Event Horizon Telescope
• Galactic Center gamma-ray "excess" from an active past of the Galactic Centre?
• Tests of General Relativity in the Strong Gravity Regime Based on X-Ray Spectropolarimetric Observations of Black Holes in X-Ray Binaries
• Testing Chern-Simons Modified Gravity with Gravitational-Wave Detections of Extreme-Mass-Ratio Binaries
• Systematic Study of Event Horizons and Pathologies of Parametrically Deformed Kerr Spacetimes
• EHT tests of the strong-field regime of General Relativity
• Nonviolent unitarization: basic postulates to soft quantum structure of black holes
• Speed of gravitational waves and black hole hair
• $f(R)$-gravity after the detection of the orbital precession of the S2 star around the Galactic centre massive black hole
• DISCO: A 3D Moving-Mesh Magnetohydrodynamics Code Designed for the Study of Astrophysical Disks
• Separating Astrophysics and Geometry in Black Hole Images
• Rotating non-Kerr black hole and energy extraction
• Anomalous decay rate of quasinormal modes
• Testing the No-Hair Theorem with Sgr A*
• GRMHD simulations of visibility amplitude variability for Event Horizon Telescope images of Sgr A*
• The Influence of Gas Dynamics on Measuring the Properties of the Black Hole in the Center of the Milky Way with Stellar Orbits and Pulsars
• Numerical black hole initial data and shadows in dynamical Chern-Simons gravity
• Shadow Geometry of Kerr Naked Singularities
• Testing the Black Hole No-hair Theorem with Galactic Center Stellar Orbits
• Constants of motion in stationary axisymmetric gravitational fields
• Probing the Spacetime Around Supermassive Black Holes with Ejected Plasma Blobs
• Extended Gravity Constraints at Different Scales
• Testing the Existence of Event Horizons against Rotating Reflecting Surfaces
• Pulsar Timing Constraints on Cumulative and Individual Mass of Stars in the Galactic Center