Gravitational Lensing

Many people think that the equation “E=mc^2” made Einstein famous but well that is not true. Einstein’s fame rose in 1919 when two expeditions observed star-light curving around the Sun during a solar eclipse in precisely the degree to which Einstein had predicted should happen if the presence of the Sun curved the space around it.

This led to the discovery of a phenomenon called “Gravitational Lensing”. It is a phenomenon in which mass bends light and magnifies it like a lens. This phenomenon has great significance in Astronomy.

The bending of light in a gravitational field could mean that if a bright object was located behind a large mass , the light rays going out in various directions could bend around the mass and converge again producing

A. Magnified image

Or

B. Numerous images of original object

This is observed a lot.

Magnified and Numerous Images

When the images were studied and the mass responsible for the curvature of light was calculated, it was observed that the most of the mass of the universe is located between the galaxies, around more that times the mass of visible matter. This was an astounding discovery which led to the theory of dark matter.