Milne, Edward Arthur (1896-1950)

English astrophysicist and mathematician. He formulated a theory of relativity which he called kinematic relativity, parallel to Albert Einstein's general theory.

Cosmological theory Milne attempted to explain the properties of the universe by kinematics (the movement of bodies). Basing his theory on Euclidean space and on Einstein's special theory of relativity alone, Milne was able to formulate systems of theoretical cosmology, dynamics, and electrodynamics. He also gave a more acceptable estimate for the overall age of the universe (10,000 million years) than that provided by the general theory of relativity.

Life Milne was born in Hull, Yorkshire, and studied at Cambridge. In 1920 he was appointed assistant director of the Solar Physics Observatory, Cambridge. He then moved to Manchester as professor of applied mathematics. From 1929 he was professor of mathematics at Oxford.

Other work Milne concentrated 1920-29 on problems of radiative equilibrium and stellar atmospheres, and provided a very clear explanation of the spectral sequence and of the photospheric temperatures and pressures involved.

He was engaged 1929-32 on stellar structure, his ideas frequently being at variance with those of Eddington and Jeans. Milne suggested that a decrease in luminosity might cause the collapse of a star, and that this could be associated with nova formation. Some of his cosmological theories were developed with Irish astrophysicist William McCrea.

From 1932 until his sudden death he devoted himself to problems of relativity and cosmology. During both world wars he was engaged in research into ballistics and sound ranging.