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arXiv · 1806.08300

A precise extragalactic test of General Relativity

Thomas E. Collett·Lindsay J. Oldham·Russell J. Smith·Matthew W. Auger·Kyle B. Westfall·David Bacon·Robert C. Nichol·Karen L. Masters·Kazuya Koyama·Remco van den Bosch
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Abstract

Einstein's theory of gravity, General Relativity, has been precisely tested on Solar System scales, but the long-range nature of gravity is still poorly constrained. The nearby strong gravitational lens, ESO 325-G004, provides a laboratory to probe the weak-field regime of gravity and measure the spatial curvature generated per unit mass, $\gamma$. By reconstructing the observed light profile of the lensed arcs and the observed spatially resolved stellar kinematics with a single self-consistent model, we conclude that $\gamma = 0.97 \pm 0.09$ at 68% confidence. Our result is consistent with the prediction of 1 from General Relativity and provides a strong extragalactic constraint on the weak-field metric of gravity.

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Thomas E. Collett, Lindsay J. Oldham, Russell J. Smith, Matthew W. Auger, Kyle B. Westfall, David Bacon, Robert C. Nichol, Karen L. Masters, Kazuya Koyama, Remco van den Bosch. 2018-06-21. A precise extragalactic test of General Relativity. https://doi.org/10.1126/science.aao2469

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