Breakdown of the Newton-Einstein Standard Gravity at Low Acceleration in Internal Dynamics of Wide Binary Stars (original) (raw)

ADS

Abstract

A gravitational anomaly is found at weak gravitational acceleration g N ≲ 10-9 m s-2 from analyses of the dynamics of wide binary stars selected from the Gaia DR3 database that have accurate distances, proper motions, and reliably inferred stellar masses. Implicit high-order multiplicities are required and the multiplicity fraction is calibrated so that binary internal motions agree statistically with Newtonian dynamics at a high enough acceleration of ≈10-8 m s-2. The observed sky-projected motions and separation are deprojected to the 3D relative velocity v and separation r through a Monte Carlo method, and a statistical relation between the Newtonian acceleration g N ≡ GM/r 2 (where M is the total mass of the binary system) and a kinematic acceleration g ≡ v 2/r is compared with the corresponding relation predicted by Newtonian dynamics. The empirical acceleration relation at ≲10-9 m s-2 systematically deviates from the Newtonian expectation. A gravitational anomaly parameter δ obs-newt between the observed acceleration at g N and the Newtonian prediction is measured to be: δ obs-newt = 0.034 ± 0.007 and 0.109 ± 0.013 at g N ≈ 10-8.91 and 10-10.15 m s-2, from the main sample of 26,615 wide binaries within 200 pc. These two deviations in the same direction represent a 10σ significance. The deviation represents a direct evidence for the breakdown of standard gravity at weak acceleration. At g N = 10-10.15 m s-2, the observed to Newton-predicted acceleration ratio is gmathrmobs/gmathrmpred=10sqrt2deltamathrmobs−mathrmnewt=1.43pm0.06{g}_{\mathrm{obs}}/{g}_{\mathrm{pred}}={10}^{\sqrt{2}{\delta }_{\mathrm{obs}-\mathrm{newt}}}=1.43\pm 0.06gmathrmobs/gmathrmpred=10sqrt2deltamathrmobsmathrmnewt=1.43pm0.06 . This systematic deviation agrees with the boost factor that the AQUAL theory predicts for kinematic accelerations in circular orbits under the Galactic external field.

Publication:

The Astrophysical Journal

Pub Date:

August 2023

DOI:

10.3847/1538-4357/ace101

10.48550/arXiv.2305.04613

arXiv:

arXiv:2305.04613

Bibcode:

2023ApJ...952..128C

Keywords:

E-Print:

A revised version of the published ApJ paper (2023, 952, 128) including corrections of Figures 12, 18, 20, and Equation (4) to be published in an erratum in press: all corrections are minor and have no impact on the contents or conclusion of the paper