Raychaudhuri equation

In general relativity, the Raychaudhuri equation, or Landau–Raychaudhuri equation,^[1] is a fundamental result describing the motion of nearby bits of matter.

The equation is important as a fundamental lemma for the Penrose–Hawking singularity theorems and for the study of exact solutions in general relativity, but has independent interest, since it offers a simple and general validation of our intuitive expectation that gravitation should be a universal attractive force between any two bits of mass–energy in general relativity, as it is in Newton's theory of gravitation.

The equation was discovered independently by the Indian physicist Amal Kumar Raychaudhuri^[2] and the Soviet physicist Lev Landau.^[3]

^ Spacetime as a deformable solid, M. O. Tahim, R. R. Landim, and C. A. S. Almeida, arXiv:0705.4120v1.
^ Dadhich, Naresh (August 2005). "Amal Kumar Raychaudhuri (1923–2005)" (PDF). Current Science. 89: 569–570.
^ The large scale structure of space-time by Stephen W. Hawking and G. F. R. Ellis, Cambridge University Press, 1973, p. 84, ISBN 0-521-09906-4.

[1] Spacetime as a deformable solid, M. O. Tahim, R. R. Landim, and C. A. S. Almeida, arXiv:0705.4120v1.

[2] Dadhich, Naresh (August 2005). "Amal Kumar Raychaudhuri (1923–2005)" (PDF). Current Science. 89: 569–570.

[3] The large scale structure of space-time by Stephen W. Hawking and G. F. R. Ellis, Cambridge University Press, 1973, p. 84, ISBN 0-521-09906-4.

[1]

[2]

[3]