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 probe the variation of G over cosmological time. We estimate constraints on 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 G today, but unfortunately extracting this information is not independent of the effort to fix other cosmological parameters such as Ho and Ωo from lensing observations.
Original language | English (US) |
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Pages (from-to) | 357-361 |
Number of pages | 5 |
Journal | Astrophysical Journal |
Volume | 397 |
Issue number | 2 |
DOIs | |
State | Published - 1992 |
Externally published | Yes |
Keywords
- Cosmology: theory
- Gravitation
- Gravitational lensing
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science