{{Short description|Belgian physicist}} '''Constantin Piron''' (1932, Paris - 9 May 2012, Lausanne) was a Belgian physicist<ref> {{cite journal |doi=10.1007/BF02057858 |bibcode = 1994FoPh...24.1107A |title=Constantin Piron at sixty-plus: Continuing a quest for the understanding of fundamental physical theories and the pursuit of their elaboration |year=1994 |last1=Aerts |first1=Diederik |journal=Foundations of Physics |volume=24 |issue=8 |pages=1107–1111 }}</ref> who worked for most of his career in Switzerland.<ref>{{cite web|url=http://takingupspacetime.wordpress.com/2012/05/15/in-memoriam-constantin-piron/ |title=In Memoriam: Constantin Piron | Taking up Spacetime |publisher=Takingupspacetime.wordpress.com |date= 16 May 2012|accessdate=2012-07-12}}</ref> In 1963 Piron earned his doctor of science degree from the University of Lausanne under the direction of Ernst Stueckelberg and Josef-Maria Jauch with a thesis on quantum logic, "Axiomatique quantique". He developed Jauch's methods (called the Geneva approach) for the foundations of quantum mechanics.
Piron's theorem (1964)<ref>{{cite journal|author=Piron, C.|title=Axiomatique Quantique|journal=Helvetica Physica Acta|year=1964|volume=37|pages=439–468}}</ref> is a famous representation theorem for quantum lattices.{{cn|date=September 2025}}
He was appointed assistant professor in the physics department of the University of Geneva in 1969 and professor ordinarius in 1974. He retired in 2000.
== Publications == * ''Observables in General Quantum Theory: Lectures Delivered at the International School of Physics "Enrico Fermi", Foundations of Quantum Mechanics'', Institut de physique théorique, 1970 *''Foundations of Quantum Physics'',<ref>{{cite journal|author=Varadarajan, V. S.|title=Review: C. Piron, ''Foundations of quantum physics''|journal=Bulletin of the American Mathematical Society |year=1977 |volume=83 |issue=2 |pages=226–231 |url=http://projecteuclid.org/euclid.bams/1183538675 |doi=10.1090/S0002-9904-1977-14275-4|doi-access=free |url-access=subscription }}</ref> W.A. Benjamin Inc., Massachusetts, 1976 *''Mécanique quantique: bases et applications'', Presses polytechniques et universitaires romandes, 1990 *''Méthodes quantiques : Champs, N-corps, diffusion'', Presses polytechniques et universitaires romandes.
==References== {{reflist}}
==External links== * {{in lang|fr}} [https://www.cpironphysicien.ch/ Page personnelle] * [http://www.genealogy.math.ndsu.nodak.edu/id.php?id=108868 His page in the Mathematics Genealogy Project] * [http://plato.stanford.edu/entries/qt-quantlog/#5 Theorem of Piron]
{{Authority control}} {{DEFAULTSORT:Piron, Constantin}} Category:Belgian physicists Category:Belgian expatriates in Switzerland Category:1932 births Category:2012 deaths Category:University of Lausanne alumni Category:Academic staff of the University of Geneva