Scale-invariant dynamics in the Solar System

Abstract

The covariant scale-invariant dynamics (SID) theory has recently been proposed as a possible explanation for the observed dynamical discrepancies in galaxies (Maeder & Gueorguiev 2020). SID implies that these discrepancies $-$ commonly attributed to dark matter $-$ arise instead from a non-standard velocity-dependent force that causes two-body near-Keplerian orbits to expand. We show that the predicted expansion of the Earth-Moon orbit is incompatible with lunar laser ranging data at $>200\sigma$. Moreover, SID predicts that the gravitating mass of any object was much smaller in the past. If true, a low-mass red giant star must be significantly older than in standard theory. This would make it much older than the conventional age of the Universe, which however is expected to be similarly old in SID. Moreover, it is not completely clear whether SID truly contains new physics beyond General Relativity, with several previous works arguing that the extra degree of freedom is purely mathematical. We conclude that the SID model is falsified at high significance by observations across a range of scales, even if it is theoretically well formulated.

5 pages, no figures, 1 table. Accepted for publication in the Monthly Notices of the Royal Astronomical Society Letters in this form

References in corpus (19)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• The Radial Acceleration Relation in Rotationally Supported Galaxies
• One Law To Rule Them All: The Radial Acceleration Relation of Galaxies
• Current status of direct dark matter detection experiments
• A Novel Test of the Modified Newtonian Dynamics with Gas Rich Galaxies
• Galaxies as simple dynamical systems: observational data disfavor dark matter and stochastic star formation
• A statistical investigation of the mass discrepancy-acceleration relation
• Fake Conformal Symmetry in Conformal Cosmological Models
• The scatter, residual correlations and curvature of the SPARC baryonic Tully-Fisher relation
• Star formation triggered by galaxy interactions in modified gravity
• A new formulation of the external field effect in MOND and numerical simulations of ultra-diffuse dwarf galaxies $-$ application to NGC 1052-DF2 and NGC 1052-DF4
• MOND as a regime of quantum gravity
• The formation of exponential disk galaxies in MOND
• Scale-Invariant Dynamics of Galaxies, MOND, Dark Matter, and the Dwarf Spheroidals
• Constraints on the HI Mass of NGC 1052-DF2
• A new line on the wide binary test of gravity
• Discussing the first velocity dispersion profile of an ultra-diffuse galaxy in MOND
• An absolute calibration system for millimeter-accuracy APOLLO measurements
• The MOND External Field Effect on the Dynamics of the Globular Clusters: General Considerations and Application to NGC 2419