Gravitational Lensing and the Variability of G

Abstract

The four observables associated with gravitational lensing of distant quasars by intervening galaxies: image splittings, relative amplifications, time delays, and optical depths, provide separate measures of the strength of the gravitational constant $G$ at cosmological distances. These allow one, in principle, to factor out unknown lensing parameters to directly to probe the variation of $G$ over cosmological time. We estimate constraints on $\dot{G}$ which may be derivable by this method both now and in the future. The limits one may obtain can compete or exceed other direct limits on $\dot{G}$ today, but unfortunately extracting this information, is not independent of the effort to fix other cosmological parameters such as $H_0$ and ${\Omega }_0$ from lensing observations.

13 pages plus figures (not included)

Cited by in corpus (10)

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• Extended Theories of Gravity and their Cosmological and Astrophysical Applications
• Reconciling dark energy models with f(R) theories
• Conformal aspects of Palatini approach in Extended Theories of Gravity
• Constraining alternative theories of gravity using GW$150914$ and GW$151226$
• Dimensionless cosmology
• Observational constraints on spatial anisotropy of G from orbital motions
• Phenomenological constraints on a scale-dependent gravitational coupling
• Constraints On Galaxy Evolution Through Gravitational Lensing Statistics
• WKB Wave Functions with the Induced Gravity Theory