XIth School of Cosmology
  17 - 22 September 2012 at IESC, Cargèse
Gravitational Lenses
their impact in the study of galaxies and
Cosmology

Microlensing of distant Quasars
Joachim WAMBSGANSS

Zentrum für Astronomie der Universität Heidelberg (ZAH)

Chapters

  1. History of Gravitational Lensing
  2. Basics of Gravitational Lensing
  3. Phenomena of Gravitational Lensing
  4. Gravitational Lensing as a tool to explore the Universe

Abstract

According to Einstein's General Theory of Relativity, a ray of light is attracted by a clump of matter. As a consequence, a light ray changes its direction from a straight line by a very small amount when it passes close to a cosmic object. This effect is called "gravitational lensing" and has four consequences:
  • Change of position
  • (De-)Magnification
  • Change of image shape
  • Occasionally multiple images
To date, a number of different lensing phenomena are known, e.g. multiple quasars, giant luminous arcs, microlensing (of stars and quasars), weak lensing, and cosmic shear. In this introductory talk the history of gravitational lensing is highlighted, and the basic concepts and phenomena are introduced.

Bibliography

    • Gravitational Lensing in Astronomy
      Wambsganss, Joachim, Living Reviews in Relativity 1 (1998), 12, URL: relativity.livingreviews.org/Articles/lrr-1998-12

Program