ڤيلم دى سيتر

Willem de Sitter
WillemDeSitter3.jpg
وُلِدَ(1872-05-06)6 مايو 1872
توفي20 نوفمبر 1934(1934-11-20) (aged 62)
Leiden, South Holland, Netherlands
الجنسيةDutch
المدرسة الأمGroningen University
اللقبde Sitter Universe
السيرة العلمية
المجالاتPhysics
المشرف على الدكتوراهJacobus Kapteyn[1]
طلاب الدكتوراهDirk Brouwer
Willem Hendrik van den Bos
التوقيع
Willem de Sitter signature.png

Willem de Sitter (6 May 1872 – 20 November 1934) was a Dutch mathematician, physicist, and astronomer.

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Life and work

Born in Sneek, de Sitter studied mathematics at the University of Groningen and then joined the Groningen astronomical laboratory. He worked at the Cape Observatory in South Africa (1897–1899). Then, in 1908, de Sitter was appointed to the chair of astronomy at Leiden University. He was director of the Leiden Observatory from 1919 until his death.

De Sitter made major contributions to the field of physical cosmology. He co-authored a paper with Albert Einstein in 1932 in which they discussed the implications of cosmological data for the curvature of the universe. He also came up with the concept of the de Sitter space and de Sitter universe, a solution for Einstein's general relativity in which there is no matter and a positive cosmological constant. This results in an exponentially expanding, empty universe. De Sitter was also famous[بحاجة لمصدر] for his research on the motions of the moons of Jupiter.[2]

Willem de Sitter died after a brief illness in November 1934.[3][4][5]


Honours

In 1912, he became a member of the Royal Netherlands Academy of Arts and Sciences.[6]

Awards

Named after him

Family

One of his sons, Ulbo de Sitter (1902 – 1980), was a Dutch geologist, and one of Ulbo's sons was a Dutch sociologist Ulbo de Sitter (1930 – 2010).

Another son of Willem, Aernout de Sitter (1905 – 15 September 1944[7]), was the director of the Bosscha Observatory in Lembang, Indonesia (then the Dutch East Indies), where he studied the Messier 4 globular cluster.

Selected publications

Einstein, Ehrenfest, Willem de Sitter, Eddington, and Lorentz in Leiden (1923)
  • De Sitter, W. (1911). "On the bearing of the Principle of Relativity on Gravitational Astronomy" . Monthly Notices of the Royal Astronomical Society. 71 (5): 388–415. doi:10.1093/mnras/71.5.388. hdl:2027/mdp.39015019246357.
  • De Sitter, W. (1913). "A proof of the constancy of the velocity of light" . Proceedings of the Royal Netherlands Academy of Arts and Sciences. 15 (II): 1297–1298. Bibcode:1913KNAB...15.1297D.
  • "On the constancy of the velocity of light" . Proceedings of the Royal Netherlands Academy of Arts and Sciences. 16 (I): 395–396. 1913.
  • De Sitter, W. (1913). "Über die Genauigkeit, innerhalb welcher die Unabhängigkeit der Lichtgeschwindigkeit von der Bewegung der Quelle behauptet werden kann"  [On the accuracy within which the independence of the speed of light from the motion of the source can be asserted]. Physikalische Zeitschrift. 14: 1267. Bibcode:1913PhyZ...14.1267D.

See also


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References

  1. ^ ڤيلم دى سيتر at the Mathematics Genealogy Project
  2. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2019-05-25. Retrieved 2019-03-11.{{cite web}}: CS1 maint: archived copy as title (link)
  3. ^ Obituary Notes of Astronomers at www.astro.uni-bonn.de
  4. ^ 1947BAN....10..287D Page 287 at articles.adsabs.harvard.edu
  5. ^ Adriaan, Blaauw (2004). "My Cruise Through the World of Astronomy". Annual Review of Astronomy and Astrophysics. 42 (1): 1–37. Bibcode:2004ARA&A..42....1B. doi:10.1146/annurev.astro.42.053102.134020.
  6. ^ "Willem de Sitter (1872 - 1934)". Royal Netherlands Academy of Arts and Sciences. Retrieved 19 July 2015.
  7. ^ Obituary Notes of Astronomers at www.astro.uni-bonn.de

External links

Wikiquote-logo.svg اقرأ اقتباسات ذات علاقة بڤيلم دى سيتر، في معرفة الاقتباس.

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Obituaries