Testing general relativity with present and future astrophysical observations

By Emanuele Berti, E. Barausse, Vitor Cardoso, L. Gualtieri, Paolo Pani, Ulrich Sperhake, Leo C. Stein, N. Wex, Kent Yagi, T. Baker and 43 more. 2015

1,331 citations recorded by the source corpus.

One century after its formulation, Einstein's general relativity (GR) has made remarkable predictions and turned out to be compatible with all experimental tests. Most of these tests probe the theory in the weak-field regime, and there are theoretical and experimental reasons to believe that GR should be modified when gravitational fields are strong and spacetime curvature is large. The best astrophysical laboratories to probe strong-field gravity are black holes and neutron stars, whether isolated or in binary systems. We review the motivations to consider extensions of GR. We present a (necessarily incomplete) catalog of modified theories of gravity for which strong-field predictions have been computed and contrasted to Einstein's theory, and we summarize our current understanding of the structure and dynamics of compact objects in these theories. We discuss current bounds on modified gravity from binary pulsar and cosmological observations, and we highlight the potential of future gravitational wave measurements to inform us on the behavior of gravity in the strong-field regime.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/aab7c98bdb322f619ff60019ae60612cda323244

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Citations in the corpus

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Dynamical boson stars (2012, background): “Much work on that front is ongoing, trying to tease out observational differences from alternative models of gravity or alternatives to the standard compact objects (BHs and NSs) [52, 53, 128].”
hi_class: Horndeski in the Cosmic Linear Anisotropy Solving System (2016, background): “This includes not only Solar-System tests, but also generation of gravitational waves, compact objects and other astrophysical tests [90] as well as, potentially, laboratory and collider experiments to connect tests of gravity on a broad range of scales [91].”
Spontaneous scalarisation of charged black holes: coupling dependence and dynamical features (2019, neutral): “the reviews [1, 2].”
Testing the rotational nature of the supermassive object M87* from the circularity and size of its first image (2019, background): “As argued in [29], this detection already qualitatively rules out several exotic alternatives to that of M87* being a “standard” Kerr BH [46,47].”
Born–Infeld inspired modifications of gravity (2017, background): “[67] for an overview on experimental constraints on the many gravitational modifications of GR proposed in the literature.”
Detecting fundamental fields with LISA observations of gravitational waves from extreme mass-ratio inspirals (2021, background): “where Ttt(t, xi) = μδ(3)(xi − zi(t)), xi are Cartesian spatial coordinates, and zi(t) is the worldline of the secondary object in these coordinates55.”
General Relativity and Cosmology: Unsolved Questions and Future Directions (2016, background): “Strong field effects PSR J0348 + 0432 [483] Black holes [411,502] Recently confirmed Binary pulsars [117]”
Approximate Universal Relations for Neutron Stars and Quark Stars (2016, methodology): “We next review applications of the universal I-Love-Q relations aimed at probing extreme gravity [278, 279, 411, 412], i.”