Blackett effect

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The Blackett effect, also called gravitational magnetism, is the hypothetical generation of a magnetic field by an uncharged, rotating body. This effect has never been observed.[ citation needed ]

History

Gravitational magnetism was proposed by the German-British physicist Arthur Schuster as an explanation for the magnetic field of the Earth, but was found nonexistent in a 1923 experiment by H. A. Wilson. [1] [2] The hypothesis was revived by the British physicist P. M. S. Blackett in 1947 when he proposed that a rotating body should generate a magnetic field proportional to its angular momentum. [3] This was never generally accepted, and by the 1950s even Blackett felt it had been refuted. [4] , pp. 3943

The Blackett effect was used by the science fiction writer James Blish in his series Cities in Flight (19551962) as the basis for his fictional stardrive, the spindizzy. [5]

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References

  1. A Critical Examination of the Possible Causes of Terrestrial Magnetism, A. Schuster, Proceedings of the Physical Society of London24 (19111912), pp. 121137.
  2. An Experiment on the Origin of the Earth's Magnetic Field, H. A. Wilson, Proceedings of the Royal Society of London, Series A104, #727 (November 1, 1923), pp. 451455.
  3. The magnetic field of massive rotating bodies, P. M. S. Blackett, Nature159, #4046 (May 17, 1947), pp. 658666.
  4. Patrick Maynard Stuart Blackett, Baron Blackett, of Chelsea, 18 November 1897-13 July 1974, Bernard Lovell, Biographical Memoirs of Fellows of the Royal Society21 (November 1975), pp. 1115.
  5. Cities in Flight, James Blish. New York: Avon, 1982. ISBN   0-380-00998-6.