Leonard Ornstein

Infobox Scientist
name = Leonard Ornstein
box_width = 250px

|300px
image_width = 150px
caption = Leonard Salomon Ornstein (1880-1941).
birth_date = November 12, 1880
birth_place = Nijmegen, The Netherlands
death_date = May 20, 1941
death_place = Utrecht, The Netherlands
residence =
citizenship =
nationality =
ethnicity = Jewish
field = Physicist
work_institutions = University of Utrecht
alma_mater = University of Leiden
doctoral_advisor = Hendrik Lorentz
doctoral_students = Marcel Minnaert
H. C. Hamaker Arie Andries Kruithof [ [http://www.genealogy.ams.org/id.php?id=110943 Arie Andries Kruithof] , Mathematics Genealogy Project.]
known_for = Ornstein-Zernike equation
Ornstein-Uhlenbeck process
author_abbrev_bot =
author_abbrev_zoo =
influences =
influenced =
prizes =
religion =
footnotes =

Leonard Salomon Ornstein (November 12, 1880, Nijmegen, The Netherlands — May 20, 1941, Utrecht, The Netherlands) [This text is almost entirely based on the article by: cite journal | last = de Lang | first = Herman | title = "Geschiedenis": 'Vuile handen' in eigen boezem | journal = [http://www.ntvn.nl/NTVN/CORE/00/01/A0.HTML Nederlands Tijdschrift voor Natuurkunde] | volume = 72 | issue = 10 | pages = 334 | publisher = [http://www.nnv.nl/ Nederlandse Natuurkundige Vereniging] | date = October 2006 | url = http://home.hetnet.nl/~alchemilab/alchemie/DeLang2.htm | accessdate = 2007-03-30 "(in Dutch").] was a Dutch physicist. He studied theoretical physics with Hendrik Antoon Lorentz at University of Leiden. He subsequently carried out Ph.D. research under the supervision of Lorentz, concerning an application of the statistical mechanics of Gibbs to molecular problems. [cite book | last = Ornstein | first = Leonard Salomon | title = Toepassing der statistische mechanica van Gibbs op molekulair-theoretische vraagstukken | publisher = Eduard IJdo | date = 1908-03-26 | location = Leiden | pages = | url = http://igitur-archive.library.uu.nl/phys/2006-0117-200056/UUindex.html | doi = | id = thesis ] In 1914 he was appointed professor of physics, as successor of Peter Debye, at University of Utrecht. In 1922 he became director of Physical Laboratory ("Fysisch Laboratorium") and extended his research interests to experimental subjects. His measurements concerning intensities of spectral lines brought Physical Laboratory in the international limelight. He is also remembered for the Ornstein-Zernike theory (named after Ornstein and Frederik Zernike) concerning correlation functions. [ [http://cbp.tnw.utwente.nl/PolymeerDictaat/node15.html The Ornstein-Zernike equation and integral equations] ] Together with Gilles Holst, ["Gilles Holst", by Albert van Helden, in K. van Berkel, A. van Helden and L. Palm, "A History of Science in The Netherlands. Survey, Themes and Reference" (Leiden: Brill, 1999), pp. 471-472. [http://www.historyofscience.nl/author.cfm?RecordId=2052 Digital Library of Royal Netherlands Academy of Arts and Sciences.] ] director of Philips Research Laboratories ("Philips Natuurkundig Laboratorium"), he was the driving force behind establishing the Dutch Physical Society ("Nederlands Natuurkundig Vereniging", NNV) in 1921. From 1939 until November 1940 he was Chairman of this Society. From 1918 until 1922 Ornstein was Chairman of the Dutch Zionist Society ("Nederlandse Zionistische Vereniging"). Immediately after the involvement of the Netherlands in the World War II (see Battle of the Netherlands), a friend from the United States of America, the astronomer Peter van de Kamp, offered to bring Ornstein and his family to America. However, Ornstein did not accept this offer, since, as he put it, he would not leave his laboratory in Utrecht. Owing to his Jewish heritage, Ornstein was summarily dismissed from University in September 1940; he was even barred from entering his own laboratory. In November 1940, he was officially dismissed from University. On his own initiative, on November 29, 1940, Ornstein withdrew his membership of the Dutch Physical Society. During this period he increasingly distanced himself from public life, to the degree that he no longer wished to receive guests at home. Ornstein died on May 20, 1941, six months after being barred from University.

One of the five buildings of Department of Physics of University of Utrecht, [http://www1.phys.uu.nl/departement/fysicacomplex/adressen/ Ornstein Laboratorium] , is named in his honor.

See also

*Uithof
*Virial coefficient

Notes

External links

*Snelders H.A.M. (2007-02-01). " [http://www.inghist.nl/Onderzoek/Projecten/BWN/lemmata/bwn2/ornstein Ornstein, Leonard Salomon (1880-1941)] ", in: "Biografisch Woordenboek van Nederland". Retrieved on 2007-03-30. "(in Dutch)".
* [http://www4.ncsu.edu/~ctk/PAPERS/OZwavelet4.pdf Multilevel wavelet solver for the Ornstein-Zernike equation Abstract]
* [http://www.iop.org/EJ/S/UNREG/lLP4nnFLwybFbk9aWg47cQ/article/0953-8984/12/38/101/c038l1.pdf Analytical solution of the Ornstein-Zernike equation for a multicomponent fluid]
* [http://www.iop.org/EJ/article/0295-5075/54/4/475/6545.html The Ornstein-Zernike equation in the canonical ensemble]