Alain Aspect (; born 15 June 1947) is a French

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate ca ...

noted for his experimental work on

quantum entanglement Quantum entanglement is the phenomenon that occurs when a group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the group cannot be described independently of the state o ...

. Aspect was awarded the 2022

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

, jointly with John Clauser and Anton Zeilinger, "for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering

quantum information science Quantum information science is an interdisciplinary field that seeks to understand the analysis, processing, and transmission of information using quantum mechanics principles. It combines the study of Information science with quantum effects in ...

Education

Aspect is a graduate of the École Normale Supérieure de Cachan (ENS Cachan, today part of

Paris-Saclay University Paris-Saclay University (french: Université Paris-Saclay) is a public research university based in Paris, France. It is one of the 13 prestigious universities that emerged from the division of the University of Paris, also known as the Sorbonne ...

). He passed the ''

agrégation In France, the ''agrégation'' () is a competitive examination for civil service in the French public education system. Candidates for the examination, or ''agrégatifs'', become ''agrégés'' once they are admitted to the position of ''profess ...

'' in physics in 1969 and received his PhD degree in 1971 from the

École supérieure d'optique The Institut d'optique Graduate School ("Institute of optics"), nicknamed SupOptique or IOGS, is one of the most prestigious French Grandes Ecoles and the leading French '' grande école'' in the field of Optics and its industrial and scientific ...

(later known as Institut d'Optique Graduate School) of

Université d'Orsay Paris-Sud University (French: ''Université Paris-Sud''), also known as University of Paris — XI (or as Université d'Orsay before 1971), was a French research university distributed among several campuses in the southern suburbs of Paris, in ...

(later known as

Université Paris-Sud Paris-Sud University (French: ''Université Paris-Sud''), also known as University of Paris — XI (or as Université d'Orsay before 1971), was a French research university distributed among several campuses in the southern suburbs of Paris, i ...

). He then taught for three years in

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west- central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; th ...

as a replacement for then compulsory military service. In the early 1980s, while working on his doctorat d'État (habilitation thesis), he performed the

Bell test experiments A Bell test, also known as Bell inequality test or Bell experiment, is a real-world physics experiment designed to test the theory of quantum mechanics in relation to Albert Einstein's concept of local realism. Named for John Stewart Bell, the ex ...

that showed that

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theor ...

Boris Podolsky Boris Yakovlevich Podolsky (russian: link=no, Бори́с Я́ковлевич Подо́льский; June 29, 1896 – November 28, 1966) was a Russian-American physicist of Jewish descent, noted for his work with Albert Einstein and Nathan ...

and

Nathan Rosen Nathan Rosen (Hebrew: נתן רוזן; March 22, 1909 – December 18, 1995) was an American-Israeli physicist noted for his study on the structure of the hydrogen atom and his work with Albert Einstein and Boris Podolsky on entangled wave functi ...

's putative

reductio ad absurdum In logic, (Latin for "reduction to absurdity"), also known as (Latin for "argument to absurdity") or ''apagogical arguments'', is the form of argument that attempts to establish a claim by showing that the opposite scenario would lead to absu ...

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, q ...

, namely that it implied ' ghostly action at a distance', did in fact appear to be realized when two

particle In the physical sciences, a particle (or corpuscule in older texts) is a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass. They vary greatly in size or quantity, fro ...

s were separated by an arbitrarily large distance (see

EPR paradox EPR may refer to: Science and technology * EPR (nuclear reactor), European Pressurised-Water Reactor * EPR paradox (Einstein–Podolsky–Rosen paradox), in physics * Earth potential rise, in electrical engineering * East Pacific Rise, a mid-oc ...

and Aspect's experiment). A correlation between the particles'

wave function A wave function in quantum physics is a mathematical description of the quantum state of an isolated quantum system. The wave function is a complex-valued probability amplitude, and the probabilities for the possible results of measurements m ...

s remains, as long as they were once part of the same undisturbed wave function before one of the child particles was measured. He defended his 'doctorat d'État' in 1983 at Université Paris-Sud (today part of Paris-Saclay University). Aspect received an honorary doctorate from

Heriot-Watt University Heriot-Watt University ( gd, Oilthigh Heriot-Watt) is a public research university based in Edinburgh, Scotland. It was established in 1821 as the School of Arts of Edinburgh, the world's first mechanics' institute, and subsequently granted uni ...

in 2008.

Research

Aspect's experiments, following the first experiment of Stuart Freedman and John Clauser in 1972, were considered to provide further support to the thesis that Bell's inequalities are violated in its

CHSH chsh (an abbreviation of "change shell") is a command on Unix-like operating systems that is used to change a login shell. Users can either supply the pathname of the shell that they wish to change to on the command line, or supply no argument ...

version, in particular by closing a form of the locality loophole. However, his results were not completely conclusive since there were loopholes that allowed for alternative explanations that comply with

local realism In physics, the principle of locality states that an object is influenced directly only by its immediate surroundings. A theory that includes the principle of locality is said to be a "local theory". This is an alternative to the concept of ins ...

. After his work on Bell's inequalities, Aspect turned toward studies of

laser cooling Laser cooling includes a number of techniques in which atoms, molecules, and small mechanical systems are cooled, often approaching temperatures near absolute zero. Laser cooling techniques rely on the fact that when an object (usually an atom) ...

of neutral atoms, and

Bose–Einstein condensate In condensed matter physics, a Bose–Einstein condensate (BEC) is a state of matter that is typically formed when a gas of bosons at very low densities is cooled to temperatures very close to absolute zero (−273.15 °C or −459.67&n ...

Aspect was deputy director of the French "

grande école A ''grande école'' () is a specialised university that is separate from, but parallel and often connected to, the main framework of the French public university system. The grandes écoles offer teaching, research and professional training in s ...

until 1994. He is a member of the

French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at th ...

and French Academy of Technologies, and a professor at the

École Polytechnique École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine The Seine ( , ) is a river in northern Franc ...

Distinctions

Aspect was elected a

Foreign Member of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemati ...

(ForMemRS) in 2015. His certificate of election reads In 2005 he was awarded the gold medal of the

Centre national de la recherche scientifique The French National Centre for Scientific Research (french: link=no, Centre national de la recherche scientifique, CNRS) is the French state research organisation and is the largest fundamental science agency in Europe. In 2016, it employed 31,637 ...

, where he is Research Director. The 2010

Wolf Prize The Wolf Prize is an international award granted in Israel, that has been presented most years since 1978 to living scientists and artists for ''"achievements in the interest of mankind and friendly relations among people ... irrespective of natio ...

in physics was awarded to Aspect, Anton Zeilinger and John Clauser. In 2013 Aspect was awarded both the

Niels Bohr International Gold Medal The Niels Bohr International Gold Medal is an international engineering award. It has been awarded since 1955 for "outstanding work by an engineer or physicist for the peaceful utilization of atomic energy". The medal is administered by the Danish ...

and the UNESCO Niels Bohr Medal. In 2011, he was assigned the Medal of the City of Paris. In 2013, he was also awarded the

Balzan Prize The International Balzan Prize Foundation awards four annual monetary prizes to people or organizations who have made outstanding achievements in the fields of humanities, natural sciences, culture, as well as for endeavours for peace and the br ...

for Quantum Information Processing and Communication. In 2014, he was named Officer of the

Legion of Honour The National Order of the Legion of Honour (french: Ordre national de la Légion d'honneur), formerly the Royal Order of the Legion of Honour ('), is the highest French order of merit, both military and civil. Established in 1802 by Napoleon ...

. Asteroid 33163 Alainaspect, discovered by astronomers at Caussols in 1998, was named after him. The official was published by the

Minor Planet Center The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory. Function ...

on 8 November 2019 (). Aspect was awarded the 2022

alongside John F. Clauser and Anton Zeilinger "for experiments with entangled photons, establishing the violation of Bell's inequalities and pioneering quantum information science".

Honours and awards

Accolades received by Aspect include the following:

Honours

* 2014: Officier of the

(

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

) * 2011: Medal of the City of Paris

Awards

* 2022:

(with John Clauser and Anton Zeilinger) * 2013:

* 2013: UNESCO Niels Bohr Medal * 2013: Frederic Ives Medal / Quinn Prize - Awards * 2012:

Albert Einstein Medal The Albert Einstein Medal is an award presented by the Albert Einstein Society in Bern. First given in 1979, the award is presented to people for "scientific findings, works, or publications related to Albert Einstein" each year. Recipients ...

* 2011: Herbert Walther award * 2010:

* 2005: CNRS Gold Medal * 1999: Gay-Lussac–Humboldt Prize * 1991: Fernand Holweck Medal and Prize * 1987: International Commission for Optics Award * 1985: Commonwealth Award for Science and Invention * 1983: ''Prix Servant''

Acknowledgement

* Member of the

Academia Europaea The Academia Europaea is a pan-European Academy of Humanities, Letters, Law, and Sciences. The Academia was founded in 1988 as a functioning Europe-wide Academy that encompasses all fields of scholarly inquiry. It acts as co-ordinator of Europea ...

* Member of the

* Member of the French Academy of Technologies * Foreign Member of the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, r ...

* Foreign Associate of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

* Associate Member of the

Royal Academy of Science, Letters and Fine Arts of Belgium The Royal Academy of Science, Letters and Fine Arts of Belgium (french: Académie royale des sciences, des lettres et des beaux-arts de Belgique, sometimes referred to as ') is the independent learned society of science and arts of the French Com ...

* Corresponding member abroad of the Austrian Academy of Sciences * Fellow of Optica

Honorary degrees

* 2006:

Université de Montréal The Université de Montréal (UdeM; ; translates to University of Montreal) is a French-language public research university in Montreal, Quebec, Canada. The university's main campus is located in the Côte-des-Neiges neighborhood of Côte- ...

* 2008:

Australian National University The Australian National University (ANU) is a public research university located in Canberra, the capital of Australia. Its main campus in Acton encompasses seven teaching and research colleges, in addition to several national academies and ...

* 2008:

* 2010:

University of Glasgow , image = UofG Coat of Arms.png , image_size = 150px , caption = Coat of arms Flag , latin_name = Universitas Glasguensis , motto = la, Via, Veritas, Vita , ...

* 2011:

University of Haifa The University of Haifa ( he, אוניברסיטת חיפה Arabic: جامعة حيفا) is a university located on Mount Carmel in Haifa, Israel. Founded in 1963, the University of Haifa received full academic accreditation in 1972, becoming I ...

* 2014:

University of Waterloo The University of Waterloo (UWaterloo, UW, or Waterloo) is a public research university with a main campus in Waterloo, Ontario, Canada. The main campus is on of land adjacent to "Uptown" Waterloo and Waterloo Park. The university also operates ...

* 2018:

City University of Hong Kong City University of Hong Kong (CityU) is a world-class public research university located in Kowloon Tong, Hong Kong. It was founded in 1984 as City Polytechnic of Hong Kong and became a fully accredited university in 1994. Currently, CityU is ...

References

Publications

* (co-author) * (Introduction) *

External links

*
Aspect's homepage

Atom Optics group
Laboratoire Charles Fabry, Institut d'Optique

at CNRS * https://web.archive.org/web/20120320235756/http://www.lcf.institutoptique.fr/Groupes-de-recherche/Optique-atomique/Membres/Membres-permanents/Alain-Aspect * http://www.academie-sciences.fr/academie/membre/Aspect_Alain.htm
Alain Aspect
International Balzan Prize Foundation
Videos of Alain Aspect
in the AV-Portal of the

German National Library of Science and Technology The German National Library of Science and Technology (german: Technische Informationsbibliothek), abbreviated TIB, is the national library of the Federal Republic of Germany for all fields of engineering, technology, and the natural sciences. I ...

* {{DEFAULTSORT:Aspect, Alain 1947 births Living people People from Agen French physicists Members of the French Academy of Sciences Wolf Prize in Physics laureates Foreign associates of the National Academy of Sciences Niels Bohr International Gold Medal recipients UNESCO Niels Bohr Medal recipients Albert Einstein Medal recipients Foreign Members of the Royal Society Members of the Royal Academy of Belgium Members of Academia Europaea Fellows of the American Physical Society Members of the Austrian Academy of Sciences École Normale Supérieure alumni École Polytechnique faculty Nobel laureates in Physics French Nobel laureates