On the Possibility of Determining Hubble's Parameter and the Masses of Galaxies from the Gravitational Lens Effect ⋆

Abstract

The gravitational lens effect is applied to a supernova lying far behind and close to the line of sight through a distant galaxy. The light from the supernova may follow two different paths to the observer, and the difference Δ t in the time of light travel for these two paths can amount to a couple of months or more, and may be measurable. It is shown that Hubble's parameter and the mass of the galaxy can be expressed by Δ t , the red-shifts of the supernova and the galaxy, the luminosities of the supernova “images” and the angle between them. The possibility of observing the phenomenon is discussed.

Author notes

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Work supported by the Norwegian Research Council for Science and the Humanities.