Emil Wolf (July 30, 1922 – June 2, 2018) was a Czech-born American

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 cau ...

who made advancements in physical

optics Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of optical instruments, instruments that use or Photodetector, detect it. Optics usually describes t ...

, including

diffraction Diffraction is the deviation of waves from straight-line propagation without any change in their energy due to an obstacle or through an aperture. The diffracting object or aperture effectively becomes a secondary source of the Wave propagation ...

coherence Coherence is, in general, a state or situation in which all the parts or ideas fit together well so that they form a united whole. More specifically, coherence, coherency, or coherent may refer to the following: Physics * Coherence (physics ...

properties of optical

fields Fields may refer to: Music *Fields (band), an indie rock band formed in 2006 * Fields (progressive rock band), a progressive rock band formed in 1971 * ''Fields'' (album), an LP by Swedish-based indie rock band Junip (2010) * "Fields", a song by ...

spectroscopy Spectroscopy is the field of study that measures and interprets electromagnetic spectra. In narrower contexts, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Spectro ...

of partially coherent

radiation In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes: * ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infr ...

, and the theory of direct scattering and inverse scattering. He was also the author of numerous other contributions to optics.

Life and career

Wolf was born into a Jewish family in

Prague Prague ( ; ) is the capital and List of cities and towns in the Czech Republic, largest city of the Czech Republic and the historical capital of Bohemia. Prague, located on the Vltava River, has a population of about 1.4 million, while its P ...

Czechoslovakia Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland beca ...

. He was forced to leave his native country when the Germans invaded. After brief periods in Italy and France (where he worked for the Czech government in exile), he moved to the United Kingdom in 1940. He received his B.Sc. in Mathematics and Physics (1945), and Ph.D. in Mathematics from

Bristol University The University of Bristol is a public research university in Bristol, England. It received its royal charter in 1909, although it can trace its roots to a Merchant Venturers' school founded in 1595 and University College, Bristol, which had ...

, England, in 1948. Between 1951 and 1954 he worked at the

University of Edinburgh The University of Edinburgh (, ; abbreviated as ''Edin.'' in Post-nominal letters, post-nominals) is a Public university, public research university based in Edinburgh, Scotland. Founded by the City of Edinburgh Council, town council under th ...

with

Max Born Max Born (; 11 December 1882 – 5 January 1970) was a German-British theoretical physicist who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics, and supervised the work of a ...

, writing the famous textbook ''

Principles of Optics ''Principles of Optics'', colloquially known as ''Born and Wolf'', is an optics textbook written by Max Born and Emil Wolf that was initially published in 1959 by Pergamon Press. After going through six editions with Pergamon Press, the book wa ...

'' now usually known simply as '' Born and Wolf''. He joined the Faculty of the

University of Manchester The University of Manchester is a public university, public research university in Manchester, England. The main campus is south of Manchester city centre, Manchester City Centre on Wilmslow Road, Oxford Road. The University of Manchester is c ...

, where he did some of his best-known work, establishing the foundations of optical coherence theory. He moved to the United States in 1959 to take a position at the

University of Rochester The University of Rochester is a private university, private research university in Rochester, New York, United States. It was founded in 1850 and moved into its current campus, next to the Genesee River in 1930. With approximately 30,000 full ...

. He became a naturalized U.S. citizen and was the Wilson Professor of Optical Physics at the University of Rochester. He was president of the

Optical Society of America Optica, founded as the Optical Society of America (later the Optical Society), is a professional society of individuals and companies with an interest in optics and photonics. It publishes journals, organizes conferences and exhibitions, and ca ...

in 1978. Until his death Wolf resided in Cloverwood in Pittsford, New York, with his wife. Wolf predicted a new mechanism that produces

redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and e ...

and

blueshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and increase in frequency and e ...

, that is not due to moving sources (

Doppler effect The Doppler effect (also Doppler shift) is the change in the frequency of a wave in relation to an observer who is moving relative to the source of the wave. The ''Doppler effect'' is named after the physicist Christian Doppler, who described ...

), that has subsequently been confirmed experimentally (called the Wolf effect). Technically, he found that two non- Lambertian sources that emit beamed energy, can interact in a way that causes a shift in the spectral lines. It is analogous to a pair of tuning forks with similar frequencies (pitches), connected together mechanically with a sounding board; there is a strong coupling that results in the resonant frequencies getting "dragged down" in pitch. The Wolf effect can produce either redshifts or blueshifts, depending on the observer's point of view, but is redshifted when the observer is head-on. A subsequent 1999 article by Sisir Roy ''et al.'' have suggested that the Wolf effect may explain discordant redshift in certain quasars. Wolf remained an active teacher, researcher and author well into his 80s. He died on June 2, 2018, aged 95.

Works

Wolf was a very well known book author in the field of optics. Along with

, he co-wrote ''

'' one of the standard textbooks of optics commonly known as "Born and Wolf". In addition he co-authored, with

Leonard Mandel Leonard Mandel (May 9, 1927 – February 9, 2001) was an American physicist who contributed to the development of theoretical and experimental modern optics and is widely considered one of the founding fathers of the field of quantum optics. With ...

, ''Optical Coherence and Quantum Optics''. He also authored ''Introduction to the Theory of Coherence and Polarization of Light'' and ''Selected Works of Emil Wolf with Commentary'' (World Scientific Publishing, 2001, ). Furthermore, he edited the '' Progress in Optics'' series of books, for

Elsevier Elsevier ( ) is a Dutch academic publishing company specializing in scientific, technical, and medical content. Its products include journals such as ''The Lancet'', ''Cell (journal), Cell'', the ScienceDirect collection of electronic journals, ...

, from its inception in 1962.

Awards, memberships and degrees

Awards

* Frederic Ives Medal of the

(1977) * Albert A. Michelson Medal of the

Franklin Institute The Franklin Institute is a science museum and a center of science education and research in Philadelphia, Pennsylvania. It is named after the American scientist and wikt:statesman, statesman Benjamin Franklin. It houses the Benjamin Franklin ...

(1980) * Max Born Award of the Optical Society of America (1987) *Marconi Medal of the Italian National Research Council (1987) *Gold Medal of the Czechoslovak Academy of Science (1991) *Medal of the Union of Czechoslovak Mathematicians and Physicists (1991) *Gold Medal of Palacký University of Olomouc, Czechoslovakia (1991) * Esther Hoffman Beller Medal (2002) * G. G. Stokes Award of

SPIE SPIE (formerly the Society of Photographic Instrumentation Engineers, later the Society of Photo-Optical Instrumentation Engineers) is an international not-for-profit professional society for optics and photonics technology, founded in 1955. It ...

(2010)

Memberships

*Honorary member of the Optical Society of America (President in 1978) *Honorary member of the Optical Societies of India and Australia

Honorary degrees

University of Groningen The University of Groningen (abbreviated as UG; , abbreviated as RUG) is a Public university#Continental Europe, public research university of more than 30,000 students in the city of Groningen (city), Groningen, Netherlands. Founded in 1614, th ...

, the Netherlands (1989) *

(1990) * Palacký University of Olomouc (1992) *

University of Bristol The University of Bristol is a public university, public research university in Bristol, England. It received its royal charter in 1909, although it can trace its roots to a Merchant Venturers' school founded in 1595 and University College, Br ...

(1997) *

Université Laval (; English: ''Laval University)'' is a public research university in Quebec City, Quebec, Canada. The university traces its roots to the Séminaire de Québec, founded by François de Montmorency-Laval in 1663, making it the oldest institutio ...

, Quebec (1997) *

University of Franche-Comté The Marie and Louis Pasteur University (UMLP), formerly known as University of Franche-Comté, is a pluridisciplinary public French university located in Besançon, Franche-Comté, with decentralized campuses in Belfort, Montbéliard, Vesoul and ...

, France (1999) *

Aalborg University Aalborg University (AAU) is an international public university with campuses in Aalborg, Esbjerg, and Copenhagen, Denmark. Founded in 1974, the university awards bachelor's degrees, master's degrees, and PhD degrees in a wide variety of subje ...

, Denmark (1999).

References

External links

Emil Wolf
Home Page at

.
''Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light (English)''
Sample chapters. *
Articles Published by early OSA Presidents
Journal of the Optical Society of America * Gregory J. Gbur (2018
RIP Emil Wolf, 1922-2018)
{{DEFAULTSORT:Wolf, Emil 1922 births 2018 deaths American physicists Optical physicists Fellows of Optica (society) Czechoslovak emigrants to the United Kingdom Czechoslovak emigrants to the United States Czech Jews Scientists from Prague Alumni of the University of Bristol University of Rochester faculty Presidents of Optica (society) Naturalized citizens of the United States Jews who immigrated to the United Kingdom to escape Nazism