Argentine physicist (1940–2021)
Miguel Ángel Virasoro (Spanish: [miˈɣel ˈaŋxel βiɾaˈsoɾo] ;9 May 1940 – 23 July 2021)[ 1] [ 2] was an Argentine (naturalized Italian [ 3] ) mathematician and theoretical physicist . Virasoro worked in Argentina , Israel , the United States , and France , but he spent most of his professional career in Italy at La Sapienza University of Rome . He shared a name with his father, the philosopher Miguel Ángel Virasoro .[ 3] He was known for his foundational work in string theory , the study of spin glasses , and his research in other areas of mathematical and statistical physics .[ 1] The Virasoro–Shapiro amplitude,[ 4] the Virasoro algebra ,[ 5] the super Virasoro algebra , the Virasoro vertex operator algebra , the Virasoro group , the Virasoro conjecture , the Virasoro conformal block , and the Virasoro minimal model are all named after him.
Biography
Early life in Argentina
Miguel Ángel Virasoro was born in Buenos Aires, Argentina in on May 9, 1940.[ 2] He shared a name with his father , a noted Argentinian philosopher who founded dialectical existentialism .[ 3] The younger Virasoro studied physics at the University of Buenos Aires (UBA) from 1958 to 1966. He received his Licenciate degree in 1962 and his PhD in 1966.[ 6]
Research in Israel and the United States
In 1966, Virasoro left Argentina after La Noche de los Bastones Largos , a violent dislodging of students and teachers from UBA who opposed the military government of Argentinian General Juan Carlos Onganía .[ 1] The military dictatorship of Onganía would last from 1966 to 1970. After leaving Argentina, Virasoro worked as a postdoctoral researcher at the Weizmann Institute of Science in Rehovot , Israel until 1968. He then worked at the University of Wisconsin-Madison (UW-M) in the United States until 1969.[ 7] After his time at UW-M, Virasoro spent another year as a postdoc in the United States at the University of California, Berkeley .
Return to Argentina
Virasoro returned to Argentina after the end of Juan Carlos Onganía's dictatorship in 1970. In 1971, he accepted a professorship at his alma mater UBA.[ 7] Virasoro remained at UBA until 1975, at which time he accepted a year-long position at the Institute for Advanced Study in Princeton, New Jersey .[ 8] Then in 1976, General Jorge Rafael Videla came to power in Argentina and established another military dictatorship. As a result, Virasoro was unable to return to his home country after his year in the United States and instead moved to Europe.[ 3]
Professional career in Europe
In Europe, Virasoro took a temporary position at the École normale supérieure in Paris, France in 1976. Virasoro then moved to Italy in 1977 where he worked as a professor at the Istituto Nazionale di Fisica Nucleare at the University of Turin from 1977 until 1981. He then moved to La Sapienza University of Rome , where he remained for thirty years until his Italian retirement and his return to Argentina in 2011.[ 3] [ 9] At La Sapienza, Virasoro performed research in mathematical physics , string theory , and statistical mechanics and taught courses on electromagnetism and on physical-mathematical models for economics.[ 10] He was also a director of the Abdus Salam International Centre for Theoretical Physics (ICTP) in Trieste, Italy from 1995 until 2002.[ 10]
Later years and death
In his later years, Virasoro received several awards, honors, and appointments. In 1987, he was awarded a Guggenheim fellowship from the John Simon Guggenheim Memorial Foundation .[ 11] In 1993, he was awarded the Rammal Award by the French Physical Society .[ 12] In 1998, he was elected as an international honorary member of the American Academy of Arts and Sciences .[ 13] In 2009, he was awarded the Enrico Fermi Prize of the Italian Physical Society , which he shared with Greek physicist Dimitri Nanopoulos , for "the discovery of an infinite-dimensional algebra of primary importance for the construction of string theories."[ 14] In 2020, he was awarded the Dirac Medal of the ICTP, which he shared with French physicists André Neveu and Pierre Ramond , "for their pioneering contributions to the inception and formulation of string theory which introduced new bosonic and fermionic symmetries into physics."[ 15]
From 2011 until his death, Virasoro was an honorary professor at the Universidad Nacional de General Sarmiento in his home country of Argentina.[ 2] [ 10] Virasoro died on July 23, 2021, at the age of 81.[ 1]
Research
String theory
Much of Virasoro's early work helped found a branch of theoretical particle physics which would later be understood as string theory . In 1968 while Virasoro was in Israel, his colleague Gabriele Veneziano discovered a formula (the Veneziano amplitude ) which described the scattering of open strings.[ 16] Then in 1969 during his time at University of Wisconsin-Madison , Virasoro successfully generalized Veneziano's theory and discovered a formula (the Virasoro-Shapiro amplitude) which described the scattering of closed strings.[ 17] At the time, the formulas of Veneziano and Virasoro were understood in terms of so-called dual resonance models . Only later was their work understood to describe strings.[ 18] [ 19]
Soon after his discovery of the Virasoro-Shapiro amplitude, Virasoro introduced what became known as the Virasoro algebra . The Virasoro algebra is an infinite-dimensional Lie algebra which describes the conformal symmetry of the worldsheet of a string embedded in spacetime . A supersymmetric generalization of this algebra, the super Virasoro algebra , describes the super conformal symmetry of the worldsheet of a supersymmetric string (or superstring). Pedagogical introductions to the Virasoro-Shapiro amplitude and the Virasoro algebra may be found in David Tong's introductory lectures on string theory.[ 20]
Several mathematical concepts related to Lie algebras and conformal field theory are named after Virasoro. These include the Virasoro vertex operator algebra , the Virasoro group , the Virasoro conjecture , the Virasoro conformal block , and the Virasoro minimal model .
Spin glasses
While working in Italy, Virasoro studied spin glasses and other systems in statistical mechanics. Together with Italian physicist Giorgio Parisi and French physicist Marc Mézard , Virasoro discovered the ultrametric organization of low-temperature spin glass states in infinite dimensions.[ 21]
References
^ a b c d "Falleció el físico Miguel Ángel Virasoro" . Facultad de Ciencias Exactas y Naturales de la Universidad de Buenos Aires (in Spanish). 2021-07-23. Retrieved 2021-07-24 .
^ a b c AEXCNdeBA. "Conocé a Miguel Ángel Virasoro | Asociación de Ex Alumnos del Colegio Nacional de Buenos Aires" (in European Spanish). Retrieved 2021-08-30 .
^ a b c d e Parisi, Giorgio (2021). "Miguel Angel Virasoro (1940-2021)" . Italian Physical Society . Retrieved August 29, 2021 .
^ Virasoro, M. (1969). "Alternative constructions of crossing-symmetric amplitudes with Regge behavior." Physical Review , 177 (5), 2309–2311.
^ M. A. Virasoro (1970). "Subsidiary conditions and ghosts in dual-resonance models". Physical Review D . 1 (10): 2933–2936. Bibcode :1970PhRvD...1.2933V . doi :10.1103/PhysRevD.1.2933 .
^ "INSPIRE" . inspirehep.net . Retrieved 2021-08-30 .
^ a b "Physics Tree - Miguel Ángel Virasoro" . academictree.org . Retrieved 2021-08-30 .
^ "Miguel Virasoro - Scholars | Institute for Advanced Study" . www.ias.edu . 2019-12-09. Retrieved 2021-08-30 .
^ "Dead Miguel Virasoro, he studied string theory – Chronicle" . Italy24 News English . 2021-07-24. Retrieved 2021-08-30 .
^ a b c "ICTP - In Memoriam" . www.ictp.it . Retrieved 2021-08-30 .
^ "John Simon Guggenheim Foundation | Miguel A. Virasoro" . Retrieved 2021-08-30 .
^ EuroScience (2000-05-22). "Rammal Award 1993-1997 granted by the French Physical Society" . EuroScience . Retrieved 2021-09-13 .
^ "Miguel Virasoro" . American Academy of Arts & Sciences . Retrieved 2021-08-30 .
^ " "Enrico Fermi" Prize" . Italian Physical Society . 2021. Retrieved August 29, 2021 .
^ Dirac Medal 2020 of ICTP
^ Veneziano, G. (1968-09-01). "Construction of a crossing-simmetric, Regge-behaved amplitude for linearly rising trajectories" . Il Nuovo Cimento A . 57 (1): 190–197. Bibcode :1968NCimA..57..190V . doi :10.1007/BF02824451 . ISSN 1826-9869 . S2CID 121211496 .
^ Virasoro, M. A. (1969-01-25). "Alternative Constructions of Crossing-Symmetric Amplitudes with Regge Behavior" . Physical Review . 177 (5): 2309–2311. Bibcode :1969PhRv..177.2309V . doi :10.1103/PhysRev.177.2309 .
^ Green, M. (2012). Superstring theory. Volume 1, Introduction. 25th anniversary edition . John H. Schwarz, E. Witten. Cambridge. ISBN 978-1-139-53120-7 . OCLC 823741954 . {{cite book }}
: CS1 maint: location missing publisher (link )
^ The Case for String Theory - Sixty Symbols , 30 January 2017, archived from the original on 2021-12-14, retrieved 2021-08-30
^ Tong, David (2012-02-23). "Lectures on String Theory". arXiv :0908.0333 [hep-th ].
^ Rammal, R.; Toulouse, G.; Virasoro, M. A. (1986-07-01). "Ultrametricity for physicists" . Reviews of Modern Physics . 58 (3): 765–788. Bibcode :1986RvMP...58..765R . doi :10.1103/RevModPhys.58.765 .
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