View source for Yoichiro Nambu

{{Short description|Japanese-American nobel-winning physicist}}
{{Use dmy dates|date=July 2015}}
{{Infobox scientist
| name              = Yoichiro Nambu<br />南部 陽一郎
| birth_date        = {{Birth date|1921|01|18|df=yes}}
| birth_place       = [[Tokyo]], [[Empire of Japan]]
| death_date        = {{death date and age|df=yes|2015|07|05|1921|01|18}}
| death_place       = [[Toyonaka, Osaka|Toyonaka]], [[Osaka]], Japan
| citizenship       = [[Americans|American]] (from 1970)
| spouse            = Chieko Hida
| children          = John Nambu (son)
| image             = YoichiroNambu.jpg
| caption           = Nambu in 2005
| field             = [[Physics]]
| alma_mater        = [[University of Tokyo|Tokyo Imperial University]]
| work_institution  = [[Imperial Japanese Army Research Institute of Technology|IJA Research Institute of Technology]] (IJA 4th Research Institute of Aeronautical Technology) (1943–45)<br>[[University of Tokyo]] (1945–49)<br>[[Osaka City University]] (1949–52)<br>[[Institute for Advanced Study]] (1952–54)<br>[[University of Chicago]] (1954–2015)<br>[[Ritsumeikan University]] (1994)<br>[[Ritsumeikan Asia Pacific University]] (1994–2015)<br>[[Osaka University]] (1996–2015)<br>[[Osaka Metropolitan University]] (2013–2015)
| known_for         = [[Spontaneous symmetry breaking]]<br>[[String theory]]<br>[[Nambu–Goto action]]<br>[[Nambu-Goldstone boson]]<br>[[Nambu mechanics]]<br>[[Nambu–Jona-Lasinio model]]
| prizes            = {{no wrap|[[Dannie Heineman Prize for Mathematical Physics|Heineman Prize]] (1970)<br>[[J. Robert Oppenheimer Memorial Prize]] (1976)<br/>[[Order of Culture]] of Japan (1978)<br>[[List of National Medal of Science laureates#Physical Sciences|US National Medal of Science]] (1982)<br />[[Max Planck Medal]] (1985)<br/>[[Dirac Medal (ICTP)|Dirac Medal]] (1986)<br />[[Sakurai Prize|J.J. Sakurai Prize]] (1994)<br />[[Wolf Prize|Wolf Prize in Physics]] (1994/1995)<br />[[Franklin Institute Awards#Benjamin Franklin Medals|Franklin Medal]] (2005)<br/>[[Pomeranchuk Prize]] (2007)<br>[[Nobel Prize in Physics]] (2008)}}
}}
{{Modern physics}}
{{Quantum field theory}}
{{Standard model of particle physics}}
{{nihongo|'''Yoichiro Nambu'''|南部 陽一郎|Nanbu Yōichirō| 18 January 1921 – 5 July 2015}} was a Japanese-American [[physicist]] and professor at the [[University of Chicago]].

Known for his groundbreaking contributions to [[theoretical physics]], Nambu was the originator of the theory of [[spontaneous symmetry breaking]], a concept that revolutionized particle physics. He was also a pioneer of [[quantum chromodynamics]] (QCD), one of the founding figures of [[string theory]], and the proposer of [[Nambu mechanics]]. In addition, he co-created the  [[Nambu–Jona-Lasinio model]], which explained the dynamical origin of mass in nucleons.

He was awarded half of the [[Nobel Prize in Physics]] in 2008 for the discovery in 1960 of the mechanism of [[Spontaneous symmetry breaking|spontaneous broken symmetry]] in [[subatomic]] physics, related at first to the [[strong interaction]]'s [[chiral symmetry]] and later to the [[electroweak interaction]] and [[Higgs mechanism]].<ref name="Nobel">{{cite web |last=Nambu |first=Yoichiro |date=2008 |url=https://www.nobelprize.org/nobel_prizes/physics/laureates/2008/nambu.html |title= Les Prix Nobel – The Nobel Prizes 2008 |editor=Karl Grandin |publisher=[[The Nobel Foundation]] |location=Stockholm |access-date=19 July 2015 |archive-date=11 October 2014 |archive-url=https://web.archive.org/web/20141011220229/http://www.nobelprize.org/nobel_prizes/physics/laureates/2008/nambu-bio.html }}</ref> The other half was split equally between [[Makoto Kobayashi (physicist)|Makoto Kobayashi]] and [[Toshihide Maskawa]] "for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature".<ref name="Nobel"/>

== Early life and education ==
Yoichiro Nambu was born on January 18, 1921, in [[Tokyo]], [[Empire of Japan]].<ref name=Ency>{{cite web|url=https://britannica.com/biography/Yoichiro-Nambu|title=Yoichiro Nambu, American physicist|publisher=// [[Encyclopædia Britannica]]|date=2015-10-13|accessdate=2016-07-06|archive-date=2016-03-25|archive-url=https://web.archive.org/web/20160325223109/http://www.britannica.com/biography/Yoichiro-Nambu|url-status=live}}</ref><ref name=NNDB>{{cite web|url=http://www.nndb.com/people/827/000177296/|title=Yoichiro Nambu|publisher=// Database [[Notable Names Database|NNDB]]|accessdate=2016-07-06|archive-date=2016-06-10|archive-url=https://web.archive.org/web/20160610102246/http://www.nndb.com/people/827/000177296/|url-status=live}}</ref> In 1923, when Tokyo was devastated by the [[Great Kanto Earthquake]], the Nambu family relocated to [[Fukui Prefecture]], the hometown of his father.<ref name=Mukerjee>{{Cite journal |author = Mukerjee M. |editor=  |format= |url= http://www.scientificamerican.com/article/profile-yoichiro-nambu/ |title= Profile: Yoichiro Nambu — Strings and Gluons, The Seer Saw Them All |journal= Scientific American  |date=  1995 |volume= 272 |issue= 2 |pages = 37–39 |doi = 10.1038/scientificamerican0295-37 |archive-url = https://web.archive.org/web/20160823070357/http://www.scientificamerican.com/article/profile-yoichiro-nambu/ |archive-date = 2016-08-23 |language= en |quote=  |url-access=subscription}}</ref> Nambu spent the rest of his childhood there and completed his high school education by age 17.

During his youth, he built a [[crystal radio]] set by himself. He later recalled being deeply moved when he was able to listen to a live [[baseball]] broadcast through the device, an early moment of fascination with science and technology.<ref>[http://www.fukuishimbun.co.jp/modules/feature/index.php?cat=87&author=33 知の巨人 南部陽一郎 （下）続け若者] {{Webarchive|url=https://web.archive.org/web/20150924040400/http://www.fukuishimbun.co.jp/modules/feature/index.php?cat=87&author=33 |date=24 September 2015 }} 『福井が育てたノーベル賞学者 南部陽一郎』 福井新聞</ref>

After graduating from high school, Nambu was admitted to the prestigious [[First Higher School]] (Ichikō), a preparatory institution for elite universities in Japan. Despite his later achievements in [[theoretical physics]], he struggled with physics during this time. He especially had difficulty understanding the concept of [[entropy]] and failed his [[thermodynamics]] course.<ref name="#1">日経サイエンス1995年4月号p.91</ref>

He went on to study at the [[Tokyo Imperial University]] (now the University of Tokyo), where [[Chushiro Hayashi]]—later known for his foundational work in astrophysics—was one of his classmates.<ref>[http://www.phys.aoyama.ac.jp/~ryo/ch18/Sato.html 第18回林忠四郎記念講演会]</ref> In his senior year, Nambu expressed interest in studying [[elementary particles]] and approached [[Hideki Yukawa]] and [[Shin'ichirō Tomonaga]] for guidance. However, he was initially turned away, being told, "Only geniuses can understand particle physics."<ref>「南部陽一郎 私の理論を理解できなかったアインシュタイン」月刊現代最終号（2009年1月）p.55</ref>

==Career==
After receiving his Bachelor of Science in 1942,<ref name="Nobel" /> Nambu was drafted into the [[Imperial Japanese Army]] in 1942. He served for one year as a [[lieutenant]] (technical lieutenant 技術中尉), engaged in tasks such as digging trenches and ferrying boats, before being assigned to a research unit focused on shortwave [[radar]] development.<ref name=Mukerjee/> During this period, he was ordered by the army to obtain a top-secret naval document written by [[Shin'ichirō Tomonaga]] on radar theory. Rather than resorting to espionage, Nambu directly approached Tomonaga and obtained the material with his cooperation.<ref name="#1"/>

Following the war, from 1945 to 1949, Nambu worked at the [[University of Tokyo]]'s Faculty of Physics. During this time, he was strongly influenced by Tomonaga's work on quantum electrodynamics and [[Ryogo Kubo]]'s studies in condensed matter physics. He earned his Doctor of Science degree in 1952.<ref name="Nobel" />

In 1949, Nambu was appointed as an associate professor at [[Osaka City University]] (now [[Osaka Metropolitan University]])<ref name="Tokyo" /> and became a full professor the following year at the age of 29.<ref name="Nobel" /> In 1952, he was invited to the [[Institute for Advanced Study]] in [[Princeton, New Jersey]], and moved to the United States. During his time there, he met [[Albert Einstein]] twice. On the second occasion, Einstein fervently attempted to explain to Nambu his deep skepticism of [[quantum mechanics]].<ref>「南部陽一郎 私の理論を理解できなかったアインシュタイン」月刊現代最終号（2009年1月）p.58</ref>

In 1954, Nambu joined the [[University of Chicago]] and was promoted to full professor in 1958.<ref>[https://web.archive.org/web/20140313001028/http://articles.chicagotribune.com/2008-10-08/news/0810070528_1_university-of-chicago-physicist-yoichiro-nambu-subatomic Chicago Tribune (October 8, 2008) "University of Chicago physicist Yoichiro Nambu wins Nobel Prize"]</ref> From 1974 to 1977, he served as Chair of the Department of Physics. He became a U.S. citizen in 1970 and remained one until his death in 2015.<ref>{{cite web|url=https://www.npr.org/templates/story/story.php?storyId=95460513|title=Chicago Professor Shares Nobel Prize In Physics|author=Matt Moore|author2=Karl Ritter|author3=Mari Yamaguchi|author4=Herbert G. McCann|name-list-style=amp |agency=[[Associated Press]]|publisher=[[NPR]]|date=7 October 2008}}</ref>

== Research ==
Nambu's research focused on [[quantum electrodynamics]], [[elementary particle]] physics, [[quantum field]] theory, [[scattering theory]], crystal statistics, and the theory of [[superconductivity]]. After more than fifty years as a professor, he was Henry Pratt Judson Distinguished Service [[Professor emeritus]] at the University of Chicago's Department of Physics and [[Enrico Fermi Institute]].<ref>{{cite web |title=Yoichiro Nambu |url=https://news.uchicago.edu/profile/yoichiro-nambu |website=The University of Chicago |archive-date=6 September 2014 |archive-url=https://web.archive.org/web/20140906173857/https://news.uchicago.edu/profile/yoichiro-nambu |url-status=dead |access-date=19 July 2015 |df=dmy-all }}</ref><ref>{{cite book |first=Brigham |last=Narins |year=2001 |title=Notable Scientists from 1900 to the Present: N-S |url=https://books.google.com/books?id=piQvAQAAIAAJ&q=nambu+henry+pratt+judson+professor+-wikipedia |page=1613 |publisher=Gale Group |isbn=9780787617554 }}</ref>

=== Spontaneous symmetry breaking ===
In 1960, he proposed the idea of [[spontaneous symmetry breaking]] (based on a formal analogy he observed between the [[Bogoliubov transformation|Bogoliubov–Valatin equations]], known in the [[BCS theory]] of superconductivity, and the [[Dirac equation]]), and also proposed the hypothesis of partial conservation of the weak axial current of [[hadrons]].

This concept provided the essential theoretical underpinning for what would eventually become the Higgs mechanism in the Standard Model, influencing the way physicists understand the origin of mass and phase transitions in field theory.

=== Nambu–Jona-Lasinio model ===
In 1961, Nambu, in two papers co-authored with Italian physicist [[Giovanni Jona-Lasinio]],<ref name=yn1>{{Cite journal |last1 = Nambu |first1=Y. |last2=Jona-Lasinio |first2=G. |format= |url= http://journals.aps.org/pr/pdf/10.1103/PhysRev.122.345 |title= Dynamical Model of Elementary Particles Based on an Analogy with Superconductivity. I |journal= Physical Review|type=  |orig-year= | agency =  |edition= Physical Review  |date=  1961 |volume= 122 |issue= 1 |pages = 345–358 |series=  |issn =  |doi = 10.1103/PhysRev.122.345 |bibcode =  1961PhRv..122..345N|arxiv =  |pmid =  |archive-url = https://web.archive.org/web/20160116222210/http://journals.aps.org/pr/pdf/10.1103/PhysRev.122.345 |archive-date = 2016-01-16 |language= en |quote=  }}</ref><ref name=yn2>{{Cite journal |author = Nambu Y., Jona-Lasinio G. |editor=  |format= |url= http://journals.aps.org/pr/pdf/10.1103/PhysRev.124.246 |title= Dynamical Model of Elementary Particles Based on an Analogy with Superconductivity. II |journal= Physical Review|type=  |orig-year= | agency =  |edition= Physical Review  |date=  1961 |volume= 124 |issue= 1 |pages = 246–254 |series=  |issn =  |doi = 10.1103/PhysRev.124.246 |bibcode =  1961PhRv..124..246N|arxiv =  |pmid =  |archive-url = https://web.archive.org/web/20190411020304/https://journals.aps.org/pr/pdf/10.1103/PhysRev.124.246 |archive-date = 2019-04-11 |language= en |quote=  }}</ref> proposed a theoretical model (now known as the [[Nambu–Jona-Lasinio model]]), in which he attempted to explain the origin of nucleon mass through the mechanism of spontaneous [[Chirality (physics)|chiral]] symmetry breaking. Later, this model was reformulated by other researchers within the framework of the [[quark]] theory of hadron structure. It turned out to be an effective computational tool for describing low-energy hadron physics, enabling, in particular, the description of [[Mass spectrum|mass spectra]] and decays of the ground states of [[meson]] nonets, as well as the study of hadron behavior in hot and dense media (which is relevant, for example, in the study of [[quark–gluon plasma]]).<ref>{{Cite journal |last1 = Волков |first1=М. К. |last2=Раджабов |first2=А. Е. |format= |url= http://ufn.ru/ru/articles/2006/6/a/ |title= Модель Намбу — Иона-Лазинио и её развитие |type=  |orig-year= | agency =  |journal= [[Успехи физических наук]]  |date=  2006 |volume= 176 |issue= 6 |pages = 569–580 |series=  |issn =  |doi = 10.3367/UFNr.0176.200606a.0569 |bibcode =  |arxiv =  |pmid =  |archive-url = https://web.archive.org/web/20080501142550/http://ufn.ru/ru/articles/2006/6/a/ |archive-date = 2008-05-01 |language= ru |quote=  |url-access=subscription|doi-access=free}}</ref>

The NJL model was later adapted by others into the framework of quark-based hadron structure theory. It proved to be a powerful computational tool for describing low-energy hadron physics, including meson mass spectra, decay modes, and behavior in hot and dense media such as the quark–gluon plasma.

=== Nambu–Goldstone theorem ===
In 1964, Nambu provided a general mathematical proof of the [[Goldstone theorem]]. The massless [[boson]]s arising in field theories with spontaneous symmetry breaking are sometimes referred to as [[Nambu–Goldstone bosons]].<ref name=yn1/><ref name=yn2/>

This theorem became a central feature of many quantum field theories and models of spontaneous symmetry breaking.

=== Quantum chromodynamics===
[[File:Yoichiro Nambu 1965.jpg|thumb|right|180px|Yoichiro Nambu was interviewed by the ''Asahi Shimbun'' in 1965.]]
In 1965, within a short interval, three works were published — a preprint by [[Nikolay Bogolyubov]], [[Boris Struminsky]],<ref>{{cite book|author=[[Boris Struminsky]] |date=1965 |location=Дубна |publisher=[[ОИЯИ]] |series=Препринты ОИЯИ, No. Р-1939 |title=Магнитные моменты барионов в модели кварков |arxiv=0904.0343 }}<!-- auto-translated from Russian by Module:CS1 translator --></ref> and [[Albert Tavkhelidze]]; a paper by Yoneji Miyamoto (宮本米二);<ref>{{Cite journal |author = Miyamoto Y. |editor=  |format= |url= http://ptps.oxfordjournals.org/content/E65/187.full.pdf |title= Three Kinds of Triplet Model |journal= Progress of Theoretical Physics Supplement|type=  |orig-year= | agency =  |edition= ''[[Progress of Theoretical Physics]]'' (Extra Number Supplement: Commemoration Issue for the Thirtieth Anniversary of the Meson Theory by Dr. H. Yukawa)  |date=  1965 |volume=  |issue=  |number= |pages = 187–192 |series=  |issn =  |doi = 10.1143/PTPS.E65.187 |bibcode =  |arxiv =  |pmid =  |language= en |quote=  }}</ref> and a paper by [[Moo-Young Han]] and Nambu.<ref>{{Cite journal |author = Han M., Nambu Y. |editor=  |format= |url= http://www.physics.princeton.edu/~kirkmcd/examples/EP/han_pr_139_B1006_65.pdf |title= Three-Triplet Model with Double SU(3) Symmetry |journal= Physical Review|type=  |orig-year= | agency =  |edition= Physical Review  |date=  1965 |volume= 139 |issue= 4B |pages = 1038–1047 |series=  |issn =  |doi = 10.1103/PhysRev.139.B1006 |bibcode =  1965PhRv..139.1006H|arxiv =  |pmid =  |archive-url = https://web.archive.org/web/20160816103416/http://www.physics.princeton.edu/~kirkmcd/examples/EP/han_pr_139_B1006_65.pdf |archive-date = 2016-08-16 |language= en |quote=  }}</ref> In these papers, the authors, analyzing various problems in quark theory, independently arrived at the idea that quarks possess a previously unknown [[quantum number]] (named "color charge" by [[Murray Gell-Mann]] and [[Harald Fritzsch]] in 1971<ref>{{Cite journal |author = Fritzsch H. |url= https://cds.cern.ch/record/1734855/files/vol52-issue8-p021-e.pdf |title= The History of QCD |type=  |orig-year= | agency =  |journal= [[:en:CERN Courier|CERN Courier]]  |year= 2012 |volume= 52 |issue= 8 |pages = 21–24 |archive-url = https://web.archive.org/web/20210829144119/https://cds.cern.ch/record/1734855/files/vol52-issue8-p021-e.pdf |archive-date = 2021-08-29 |language= en |quote=  }}</ref>). They also developed a model of [[strong interactions]] based on three triplets of quarks with integer [[electric charges]].<ref>{{cite book|archive-date=2016-10-11 |archive-url=https://web.archive.org/web/20161011190047/http://www.inr.ac.ru/a/history/6/cq.pdf |author=[[Viktor Matveev]], [[Albert Tavkhelidze]] |date=2005 |location=Дубна |pages=19 |publisher=[[ОИЯИ]] |series=Препринты ОИЯИ, No. Д2-2005-164 |title=Квантовое число — цвет, цветные кварки и КХД (к 40-летию открытия квантового числа — цвет) |url=http://www.inr.ac.ru/a/history/6/cq.pdf}}<!-- auto-translated from Russian by Module:CS1 translator --></ref> Nambu proposed the idea of "color charge" of [[quantum chromodynamics]],<ref>{{cite book |first1=Raymond |last1=Serway |first2=Clement |last2=Moses |first3=Curt |last3=Moyer |year=2004 |chapter-url=https://books.google.com/books?id=uTM8AAAAQBAJ&q=Yoichiro+Nambu+color+charge+quantum+-wikipedia&pg=PA577 |chapter=Elementary Particles |url=https://books.google.com/books?id=uTM8AAAAQBAJ |page=577 |title=Modern Physics |edition=3rd |publisher=Thomson Learning |access-date=19 July 2015 |via=[[Google Books]] |isbn=1111794375 }}</ref> building on his earlier work on spontaneous symmetry breaking in particle physics.<ref>{{cite book |author1=Xing, Zhizhong |author2=Shun Zhou |year=2011 |chapter-url=https://books.google.com/books?id=6QXqlCHLjJkC&q=Yoichiro+Nambu+spontaneous+symmetry+-wikipedia&pg=PA23 |chapter=Neutrinos within the Standard Model |title=Neutrinos in Particle Physics, Astronomy and Cosmology |page=23 |publisher=[[Zhejiang University Press]] |isbn=9783642175602 |access-date=19 July 2015 |via=Google Books }}</ref>

Although later versions of the Standard Model adopted fractional charges, Nambu's proposal of color as a quantum degree of freedom laid the conceptual groundwork for the development of quantum chromodynamics (QCD), the modern theory of strong interactions.

=== String theory ===
In the early 1970s, Nambu independently discovered that the [[dual resonance model]], originally introduced to describe hadronic scattering amplitudes, could be reinterpreted as a theory of quantized relativistic strings. This insight provided the first theoretical framework in which extended one-dimensional objects, rather than point particles, were used to explain the behavior of fundamental interactions.<ref>Nambu, Y. (1970). "Quark model and the factorization of the Veneziano amplitude." In R. Chand (ed.), ''Symmetries and quark models'' (pp. 269–277). Singapore: World Scientific.</ref><ref>{{cite book |first=Peter |last=Pesic |year=2014 |chapter-url=https://books.google.com/books?id=HfPvAwAAQBAJ&q=Yoichiro+Nambu+dual+resonance+model+-wikipedia&pg=PA279 |chapter=Unheard Harmonies |title=Music and the Making of Modern Science |url=https://books.google.com/books?id=HfPvAwAAQBAJ |publisher=[[Massachusetts Institute of Technology Press]] |access-date=19 July 2015 |via=Google Books |isbn=9780262027274 }}</ref> His reformulation laid the groundwork for the development of [[bosonic string theory]], and he is widely recognized as one of the founding figures of string theory.<ref>{{cite book |first1=Andrew Zimmerman |last1=Jones |first2=Daniel |last2=Robbins |year=2010 |chapter=Ten Notable String Theorists |chapter-url=https://books.google.com/books?id=uS6UHlSN54EC&q=nambu+founders+string+theory+-wikipedia&pg=PA347 |page=347 |title=String Theory for Dummies |url=https://books.google.com/books?id=uS6UHlSN54EC |location=[[Hoboken, New Jersey]] |publisher=[[Wiley Publishing]] |access-date=19 July 2015 |via=Google Books |isbn=9780470595848 }}</ref>

One of his key contributions was the introduction of the action principle for strings, now known as the [[Nambu–Goto action]], which describes the dynamics of a relativistic string as the area of the worldsheet swept out in spacetime. This formalism became a central component of modern string theory, influencing later developments in [[superstring theory]], [[M-theory]], and attempts to unify [[quantum mechanics]] with general relativity.

=== Nambu mechanics ===
In 1973, Nambu proposed a generalization of [[Hamiltonian mechanics]] now known as [[Nambu mechanics]].<ref>{{cite journal |author-link=Yoichiro Nambu |first=Y. |last=Nambu |title=Generalized Hamiltonian dynamics |journal=[[Physical Review D]] |volume=7 |year=1973 |issue= 8|pages=2405–2412 |doi=10.1103/PhysRevD.7.2405 |bibcode = 1973PhRvD...7.2405N }}</ref> This formulation extended classical dynamics by introducing multiple Hamiltonian functions and a higher-order structure called the Nambu bracket. Unlike traditional Hamiltonian systems that use a single Hamiltonian and a [[Poisson bracket]], Nambu mechanics allows the evolution of physical systems to be described using ternary (or higher) brackets with multiple conserved quantities.

Though initially overlooked, Nambu mechanics later gained attention in the study of non-linear systems, [[fluid dynamics]], and higher-dimensional theoretical frameworks. It has influenced areas such as [[quantum]] Nambu brackets, generalized integrable systems, and has been discussed in the context of string theory and [[M-theory]] as a potential mathematical structure underlying extended objects like membranes.

=== Other early contributions in particle physics ===
Nambu's early work laid essential groundwork for his later breakthroughs:
*In 1951, he independently proposed the concept of associative production of strange particles, explaining their appearance in high-energy collisions.
*In 1957, he predicted the existence of the vector [[omega meson]], and derived a fundamental relation known as crossing symmetry, which became a key tool in analyzing particle interactions.<ref>{{Cite journal |author = Nambu Y. |editor=  |format= |url= https://archive.org/details/sim_physical-review_1957-06-15_106_6/page/n254 |title= Possible Existence of a Heavy Neutral Meson |journal= Physical Review|type=  |orig-year= | agency =  |edition= Physical Review  |date=  1957 |volume= 106 |issue= 6 |pages = 1366–1367 |series=  |issn =  |doi = 10.1103/PhysRev.106.1366 |bibcode =  1957PhRv..106.1366N|arxiv =  |pmid =  |language= en |quote=  }}</ref>

== Later career in Japan  ==
In 1994, Yoichiro Nambu was appointed as a visiting professor at [[Ritsumeikan University]] and an academic advisor at [[Ritsumeikan Asia Pacific University]]. That same year, the two institutions established the Yoichiro Nambu Research Encouragement Fund. In 1996, he received the first honorary doctorate awarded by [[Osaka University]] (UOsaka), and in 2006, he became a specially appointed professor there. He held a research office on the UOsaka Toyonaka Campus.<ref>[https://nambu-memorial.sci.osaka-u.ac.jp/university/index.html 大阪大学と南部陽一郎{{pipe}}大阪大学 大学院理学研究科・理学部 南部陽一郎記念室]</ref>

On November 12, 2010, Nambu made a special appearance at a celebration held for [[Purdue University]] professor [[Ei-ichi Negishi]], who had received the 2010 [[Nobel Prize in Chemistry]]. Both men were [[List of Japanese Nobel laureates and nominees|Japanese Nobel laureates]] residing in the American Midwest and alumni of the [[University of Tokyo]].<ref>{{Cite web |url=http://www.47news.jp/CN/201011/CN2010111301000326.html |title=ノーベル賞の根岸英一さんを祝福 南部陽一郎さんら、米で祝賀会 - 47NEWS（よんななニュース） |accessdate=2015-04-23 |archive-date=2015-05-26 |archive-url=https://web.archive.org/web/20150526064242/http://www.47news.jp/CN/201011/CN2010111301000326.html |url-status=live }}</ref>

In 2011, Nambu returned to Japan and settled permanently in [[Toyonaka]], Osaka Prefecture. He continued his affiliation with Osaka University. The '''Nambu Hall''' was opened on the second floor of the J Building, Graduate School of Science, in 2017.<ref>[https://www.sci.osaka-u.ac.jp/ja/nambu-hall/ 南部陽一郎ホール – 大阪大学 大学院理学研究科・理学部]</ref>

Nambu also held the titles of Honorary Professor and Special Distinguished Professor at [[Osaka City University]] (now [[Osaka Metropolitan University]]). The university later established the '''Nambu Yoichiro Institute of Theoretical and Experimental Physics''' (NITEP) on November 1, 2018.<ref>[https://www.nitep.omu.ac.jp/en/about.html Nambu Yoichiro Institute of Theoretical and Experimental Physics (NITEP){{pipe}}about NITEP]</ref>

==Family and popular culture==
Yoichiro's father, {{nihongo|Kichiro Nambu|南部 吉郎|Nanbu Kichirō}}, was originally from Fukui and attended [[Ritsumeikan Uji Junior and Senior High School|Ritsumeikan Middle School]] before going on to study literature at [[Waseda University]]. His graduation thesis focused on [[William Blake]], the English poet, painter, and printmaker. The following year, in 1921, Yoichiro was born in Tokyo. However, after the [[Great Kanto Earthquake]] struck in 1923, the family of three returned to Fukui, where Kichiro took up a position as an English teacher at [[List of high schools in Fukui Prefecture|Fukui Girls' High School]].

The name of {{nihongo|Dr. Kozaburo Nambu|南部 考三郎|Nanbu Kōzaburō}}, one of the main characters in the famous Japanese anime ''[[Science Ninja Team Gatchaman]]'', was inspired by Yoichiro Nambu.<ref>[EP.247 史上最具創造力的物理學家：南部陽一郎登場！（量...–熱血科學家的閒話加長（The Excited Scientists' Hot Tea） – Apple Podcasts https://podcasts.apple.com/tw/podcast/ep-247-%E5%8F%B2%E4%B8%8A%E6%9C%80%E5%85%B7%E5%89%B5%E9%80%A0%E5%8A%9B%E7%9A%84%E7%89%A9%E7%90%86%E5%AD%B8%E5%AE%B6-%E5%8D%97%E9%83%A8%E9%99%BD%E4%B8%80%E9%83%8E%E7%99%BB%E5%A0%B4-%E9%87%8F%E5%AD%90%E7%86%8A-76/id1548260327?i=1000709420884&l=en-GB]</ref>

== Death ==
Nambu died of [[heart failure]] at the hospital in Osaka on 5 July 2015, at the age of 94, and  his death was announced 12 days later.<ref name=grimes>{{citation |last=Grimes |first=William |title=Yoichiro Nambu, Nobel-Winning Physicist, Dies at 94 | newspaper=[[The New York Times]] |date=17 July 2015 |url=https://www.nytimes.com/2015/07/18/us/yoichiro-nambu-nobel-winning-physicist-dies-at-94.html}}</ref><ref name="Japanese obit">{{Cite web|title = 南部陽一郎 大阪大学特別栄誉教授のご逝去について|url = http://www.osaka-u.ac.jp/ja/news/topics/2015/07/20150717_01|website = 大阪大学|access-date = 17 July 2015}}</ref><ref>{{cite news | title = 2008年ノーベル物理学賞受賞の南部陽一郎 大阪大学特別栄誉教授がご逝去されました | publisher = [[Osaka University]] | date = 17 July 2015 | url = http://www.osaka-u.ac.jp/ja/news/topics/2015/07/20150717_01 | access-date = 17 July 2015}}</ref><ref>{{cite news |title=Nobel laureate in physics, Yoichiro Nambu dies at 94 |url=http://www.laprensasa.com/309_america-in-english/3229007_nobel-laureate-in-physics-yoichiro-nambu-dies-at-94.html |agency=[[EFE]] |website=[[La Prensa de San Antonio]] |date=17 July 2015 |access-date=18 July 2015 |url-status=dead |archive-url=https://web.archive.org/web/20150721210113/http://www.laprensasa.com/309_america-in-english/3229007_nobel-laureate-in-physics-yoichiro-nambu-dies-at-94.html |archive-date=21 July 2015 |df=dmy-all }}</ref> His funeral and memorial services were held among close relatives.<ref name="Japanese obit"/>

Nambu was survived by his wife, Chieko, and his son, John.<ref name="Japanese obit"/>

== Recognition ==
[[File:NambuDualityMeetingArgonne1996.jpg|400px|thumb| Nambu (white shirt) and associates in 1996]] 
In 2008, although awarded the [[Nobel Prize in Physics]], Nambu did not travel to [[Stockholm]] to attend the award ceremony. At his request, his former colleague [[Giovanni Jona-Lasinio]] traveled in his place and graciously delivered the Nobel Lecture on his behalf.<ref>{{Cite web | url=https://www.nobelprize.org/prizes/physics/2008/nambu/lecture/ | title=The official website of the Nobel Prize}}</ref>

[[Bruno Zumino]], one of the founders of [[supersymmetry]], once remarked:
<blockquote>"He was always ten years ahead of us, so I tried to understand his work in order to contribute to a field that would flourish a decade later. But contrary to my expectation, it took me ten years just to understand what he had done."<ref>{{Cite web |url=http://www.worldscientific.com/doi/pdf/10.1142/9789813108332_fmatter |title=存档副本 |doi=10.1142/9789813108332_fmatter |access-date=2016-11-17 |archive-date=2019-05-03 |archive-url=https://web.archive.org/web/20190503013905/https://www.worldscientific.com/doi/pdf/10.1142/9789813108332_fmatter |url-status=live }}</ref></blockquote>

[[Toshihide Maskawa]], Nobel Prize laureate in Physics, once stated:
<blockquote>
"Professor Nambu is the greatest physicist Japan has ever produced. I believe he stands even above [[Hideki Yukawa]] and [[Shin'ichirō Tomonaga]]."<ref>{{cite web|url=http://www.sankei.com/west/news/150717/wst1507170084-n1.html|title=「湯川、朝永先生より上」と益川敏英・京産大教授|work=産経WEST|date=2015-07-17|accessdate=2015-07-17|archive-date=2015-07-20|archive-url=https://web.archive.org/web/20150720220223/http://www.sankei.com/west/news/150717/wst1507170084-n1.html|url-status=live}}</ref> "Japan's Nobel-winning physicists are all brilliant, and I know them well—but if I had to name a true 'genius,' it would be Yoichiro Nambu."<ref>「大発見」の思考法 (文春新書)</ref></blockquote>

===Awards===
* 1970: [[Dannie Heineman Prize for Mathematical Physics|Dannie Heineman Prize]]
* 1977: [[J. Robert Oppenheimer Memorial Prize]]<ref>{{cite book| title= Winners, the blue ribbon encyclopedia of awards | url= https://archive.org/details/winnersblueribbo0000walt | url-access= registration |last=Walter |first=Claire |date=1982 |page= [https://archive.org/details/winnersblueribbo0000walt/page/438 438]|publisher=Facts on File Inc.|isbn=9780871963864 }}</ref><ref>{{cite journal |author=<!--Staff writer(s); no by-line.--> |title=J. Robert Oppenheimer Prize awarded to Yoichiro Nambu |journal=Physics Today |volume=29 |issue=3 |pages=76–78 |publisher=American Institute of Physics |date=March 1976 |doi=10.1063/1.3023388 }}</ref>
* 1982: [[National Medal of Science]]
* 1985: [[Max Planck Medal]], Germany
* 1986: [[Dirac Medal (ICTP)|Dirac Prize]]
* 1994: [[Sakurai Prize]]
* 1994/1995: [[Wolf Prize in Physics]]
* 2005: [[Benjamin Franklin Medal (Franklin Institute)|Benjamin Franklin Medal]], [[Franklin Institute]]<ref name=Tokyo>{{cite web |first=Tetsuo |last=Hatsuda |url=http://www.s.u-tokyo.ac.jp/en/research/alumni/nambu/ |title=Notable Alumni: Yoichiro Nambu |website=University of Tokyo |url-status=live |archive-date=19 July 2015 |archive-url=https://web.archive.org/web/20150719152217/http://www.s.u-tokyo.ac.jp/en/research/alumni/nambu/ |access-date=19 July 2015 }}</ref><ref>{{cite web |date=April 2005 |title=Yoichiro Nambu |url=https://www.fi.edu/laureates/yoichiro-nambu |website=[[Franklin Institute]] |url-status=live |archive-date=14 May 2015 |archive-url=https://web.archive.org/web/20150514042400/https://www.fi.edu/laureates/yoichiro-nambu |access-date=19 July 2015 }}</ref>
* 2005: [[Oskar Klein Memorial Lecture]]
* 2007: [[Pomeranchuk Prize]]
* 2008: [[Nobel Prize in Physics]] "for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics".<ref name="Nobel" /><ref>{{cite web|url=https://news.bbc.co.uk/1/hi/sci/tech/7656538.stm|title=Cosmic imperfections celebrated|author=Jonathan Amos|date=7 October 2008|publisher=[[BBC]]}}</ref><ref name=pollard>{{Cite news |last=Pollard|first=Niklas |title=Two Japanese, American win 2008 physics Nobel  | work=[[Reuters]] |date=7 October 2008 |url=https://www.reuters.com/article/scienceNews/idUSTRE4963JJ20081007 }}</ref>

===Honors===
* 1978: [[File:JPN Bunka-kunsho BAR.svg|45px|ribbon bar]] [[Order of Culture]], Japan
* 1978: [[Person of Cultural Merit]], Japan
* 1979: Honorary Citizen of [[Fukui City]], Japan<ref>[http://www.city.fukui.lg.jp/sisei/fukuisi/meiyosimin/honor_citizen.html 福井市名誉市民・市民栄誉賞] 福井市 2008年10月11日 閲覧{{in lang|ja}}</ref>
* 2003: Fukui Prefectural Award, Japan<ref>{{Cite web |url=http://www.city.fukui.lg.jp/sisei/fukuisi/meiyosimin/nambu-yoichiro.html |title=名誉市民の南部陽一郎先生が逝去されました。 福井市ホームページ |access-date=30 May 2024 |archive-date=23 September 2015 |archive-url=https://web.archive.org/web/20150923203946/http://www.city.fukui.lg.jp/sisei/fukuisi/meiyosimin/nambu-yoichiro.html |url-status=bot: unknown }}2015年8月11日 閲覧{{in lang|ja}}</ref>
* 2011: Honorary Citizen of [[Toyonaka City]], Japan<ref>{{Cite web|title=南部陽一郎さん（平成23年9月7日 豊中市議会議決） 豊中市|url=https://www.city.toyonaka.osaka.jp/joho/shoukai/meiyosimin/meiyosimin/nanbu_yoichiro/001nanbu.html|website=www.city.toyonaka.osaka.jp|accessdate=2021-06-01}}</ref>

==Bibliography==
* Nambu, Yoichiro (1985), ''Quarks'', Singapore: World Scientific.

==See also==
* [[List of Japanese Nobel laureates]]
* [[List of Nobel laureates affiliated with the University of Tokyo]]

== References ==
{{Reflist|30em}}

== External links ==
{{wikiquote}}
* [https://www.aip.org/history-programs/niels-bohr-library/oral-histories/30538 Oral history interview with Yoichiro Nambu on 16 July 2004, American Institute of Physics, Niels Bohr Library & Archives]
* [https://archive.today/20121210104545/http://physics.uchicago.edu/research/areas/particle_t.html#Nambu Yoichiro Nambu, Department of Physics faculty profile, University of Chicago]
* [http://www.scientificamerican.com/article/profile-yoichiro-nambu/ Profile, Scientific American Magazine]
* [http://www.fi.edu/winners/2005/nambu_yoichiro.faw?winner_id=4394  Yoichiro Nambu, Sc.D. Biographical Information] {{Webarchive|url=https://web.archive.org/web/20081010214706/http://www.fi.edu/winners/2005/nambu_yoichiro.faw?winner_id=4394 |date=10 October 2008 }}
* [https://inspirehep.net/literature?sort=mostcited&size=25&page=1&q=a%20yoichiro%20nambu Nambu's most-cited scientific papers]
* [http://www.worldscibooks.com/general/0103.html Yoichiro Nambu's earliest book for the scientific layman] {{Webarchive|url=https://web.archive.org/web/20110629121601/http://www.worldscibooks.com/general/0103.html |date=29 June 2011 }}
* [http://www.worldscibooks.com/physics/2840.html Yoichiro Nambu's previously unpublished material, including an original article on spontaneously broken symmetry]
* [http://www.sciam.com/article.cfm?id=physicists-in-wartime-japan "A History of Nobel Physicists from Wartime Japan"  Article published in the December 1998 issue of Scientific American, co-authored by Laurie Brown and Yoichiro Nambu]
*[http://www.huffingtonpost.com/madhusree-mukerjee/the-passing-of-a-gentle-g_b_7827966.html Tribute upon Prof. Nambu passing by former student Dr. Madhusree Mukerjee]
*[https://www.lib.uchicago.edu/e/scrc/findingaids/view.php?eadid=ICU.SPCL.NAMBUY Guide to the Yoichiro Nambu Papers 1917-2009] at the [https://www.lib.uchicago.edu/scrc/ University of Chicago Special Collections Research Center]
* {{Nobelprize}}

{{Winners of the National Medal of Science|physical}}
{{Wolf Prize in Physics}}
{{2008 Nobel Prize winners}}

{{Nobel Prize in Physics Laureates 2001-2025}}

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[[Category:J. J. Sakurai Prize for Theoretical Particle Physics recipients]]
[[Category:Winners of the Max Planck Medal]]
[[Category:Benjamin Franklin Medal (Franklin Institute) laureates]]