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Arthur Eddington

1882 - 1944

Arthur Eddington, 1882 - 1944, English physicist

Arthur Stanley Eddington, 1882 - 1944, was an English astronomer, best known for his confirmation of Einstein's General Relativity Theory, by measuring the gravitational lensing of the Sun during a solar eclipse on 29 May, 1919.

  • Nationality
  • English

  • Subject
  • Astronomy

  • Fields
  • Relativity, stellar luminosity, philosophy of science

  • Distinctions
  • Eddington received many honours, including the Royal Medal, Royal Society (Member since 1914), 1928.

  • Posts
  • Post-graduate researcher at the Cavendish Laboratory, Physics Department, Cambridge, 1905.

    Chief assistant to the Astronomer Royal at Royal Greenwich Observatory, 1906.

    Plumian Professor of Astronomy and Experimental Philosophy, Cambridge University 1913.

    Director of Cambridge Observatory, 1914.

    Secretary of the Royal Astronomical Society during World War One. It was in this role that he received, via Willen de Sitter, papers and letters concerning Albert Einstein's General Relativity.

  • Publications
  • The Internal Constitution of Stars, 1926, summarising his groundbreaking work revolutionising stellar evolution theory.

  • Theories
  • Stellar processes and explanation of Cepheid variable stars.

    Extension to Karl Schwarzschild's work on radiation pressure in Emden polytropic models, in which stars maintain their size by a equilibrium between gravity and internal thermal pressure.

    Eddington vehemently opposed Subrahmanyan Chandrasekhar's extension of his work to a theoretical description of black holes, considering the idea full of physical paradoxes.

  • Equations
  • Mass-luminosity relation, which describe most stars as showing ideal gas behaviour, a radical concept at the time, bringing him into conflict with established scientists such as James Jeans. He calculated the internal temperature of stars as millions of degrees.

  • Experiments/Discoveries
  • Measurement of the curvature of space around the Sun, May 1919, to confirm Einstein's General Relativity Theory, which catapulted Einstein into fame and history.

Gravity lens
Einstein became famous when it was proved that light is bent around stars by gravity, as he predicted in his Theory of Relativity.

Eddington led an expedition to the South Atlantic to measure the degree to which light is bent around the Sun, possible only during a total solar eclipse. This went against Newton's Universal Law of Gravitation, and confirmed Einstein's General Relativity. A previous attempt to do this experiment had been frustrated by the outbreak of the First World War.

Eddington brought Einstein's theory to the English-speaking world through a series of articles, at a time when German scientists were being ostracised, during and after World War One. Both scientists were engaged in breaking down the post-war prejudice, and allowing a renewal of the flow of cooperation between scientists from Germany and the rest of the world.

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