James MacCullagh

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James MacCullagh.

James MacCullagh (* 1809 in Landahaussy near Strabane , † October 24, 1847 in Dublin ) was an Irish mathematician and physicist .

Life

MacCullagh was born in Landahaussy, near Strabane , County Tyrone , in 1809 and attended Trinity College in Dublin from 1824 to 1829, which was also where William Rowan Hamilton was at that time . In 1832 he won a fellowship and became a mathematical assistant and then mathematics professor at Trinity College (from 1843 professor for "Natural Philosophy", ie theoretical physics ). In 1843 he became a member of the Royal Society after receiving their Copley Medal a year earlier . MacCullagh died of suicide in Dublin after a letter to Hamilton two years earlier complaining of a decline in his math skills. His collected works were published in Dublin in 1880.

plant

Most of his time he spent doing research on optics in connection with the theory of diffraction and refraction, treating Fresnel's wave theory using geometric methods. But William Rowan Hamilton and Franz Ernst Neumann came before him for two important works on crystal optics , which led to disputes over priority. In 1839 he gave a theory of the ether as an elastic medium for the propagation of light, which indeed reproduced the reflection and refraction in crystals well, but was rejected by his contemporaries because it seemed to imply a rotation of the medium against absolute space. It was not until 40 years later that George Francis FitzGerald pointed out that MacCullogh, with his equations presented in 1839, anticipated the Maxwell equations published in 1864 in the case under consideration. Best known to his contemporaries, however, were his contributions to geometry ( On surfaces of the second order 1843).

MacCullagh corresponded with John Herschel and Charles Babbage , who wrote that MacCullagh had been an excellent friend of his with whom he discussed the benefits and implications of the Analytical Engine .

See also

literature

  • Scaife James MacCullagh , Proceedings Royal Irish Academy Vol. 90 C, 1990, p. 67
  • Felix Klein Development of Mathematics in the 19th Century , Vol. 1, p. 231
  • Whittaker History of the theories of ether and electricity , Vol. 1, 1910
  • MacCullagh: Collected Works , Dublin, London 1880 (Eds. Samuel Haughton, John Hewitt Jellett ), Archives

Web links

Remarks

  1. ↑ An essay toward the dynamical theory of reflexion and refraction , published in 1848 in Dublin Transactions Vol. 21
  2. ↑ See also the discussion in: "The quasi-elastic body as an ether model" - Section 15 of Chapter III in: Mechanics of deformable media by Arnold Sommerfeld . - 5th edition / edited and supplemented by Erwin Fues and Ekkehart Kröner - Leipzig: Geest & Portig, 1964. (Lectures on theoretical physics; Volume 2, Ed.5) p. 96 ff
  3. ^ Whittaker History of the theories of ether and electricity Vol. 1, 1910, pp. 289, 295, and on MacCullogh's theory of 1839, especially p. 154
personal data
SURNAME MacCullagh, James
BRIEF DESCRIPTION Irish mathematician and physicist
DATE OF BIRTH 1809
PLACE OF BIRTH Landahaussy near Strabane
DATE OF DEATH October 24, 1847
Place of death Dublin