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{{Infobox scientist
Hi there. Allow me begin by introducing the author, her name is Myrtle Cleary. For a while she's been in South Dakota. Managing individuals is his occupation. The preferred hobby for my kids and me is to perform baseball and I'm trying to make it a occupation.<br><br>My web site - [http://Theoffshoremanual.com/?testimonial=know-facing-candida-albicans Theoffshoremanual.com]
|name              = John Clive Ward
|image            =
|width            =
|birth_date        = {{Birth date|1924|08|01}}
|birth_place      = [[London]], [[England]]
|nationality      = [[Australia]]n, [[United Kingdom|British]]
|death_date        = {{Death date and age|2000|05|06|1924|8|1}}
|death_place      = [[Victoria, British Columbia|Victoria]], [[British Columbia]]
|field            = [[Particle Physics]]
|alma_mater        = [[University of Oxford]]
|doctoral_advisor  = [[Maurice Pryce|Maurice H. L. Pryce]]
|notable_students  = [[F. J. Duarte]]
|work_institutions = [[Institute for Advanced Study]]<br>[[Bell Laboratories]]<br>[[University of Adelaide]]<br>[[University of Maryland]]<br>[[University of Miami]]<br>[[Carnegie Institute of Technology]]<br>[[Johns Hopkins University]]<br>[[Victoria University of Wellington]]<br>[[Macquarie University]]
|known_for        = [[Electroweak theory]]<br>[[Quantum electrodynamics]]<br>[[Quantum field theory]]<br>[[Renormalization|Renormalization theory]]<br>[[Ward–Takahashi identity]]
|prizes            = [[Guthrie Medal and Prize|Guthrie Medal]] (1981)<br>[[Dirac Prize|Dirac Medal]] (1981)<br>[[Dannie Heineman Prize for Mathematical Physics|Heineman Prize]] (1982)<br>  [[Hughes Medal]] (1983)
 
}}
 
'''John Clive Ward''' (August 1, 1924 – May 6, 2000) was a [[United Kingdom|British]]-[[Australia]]n [[physicist]]. His most famous creation was the [[Ward–Takahashi identity]], originally known as "Ward Identity" (or "Ward Identities").<ref>{{cite journal|author=J. C. Ward|title=An identity in quantum electrodynamics|journal=Phys. Rev|volume=78|pages=182|year=1950|url=http://prola.aps.org/abstract/PR/v78/i2/p182_1|doi=10.1103/PhysRev.78.182}}</ref><ref>{{cite journal|author=Dalitz, Richard H.|author2=Duarte, Frank J.|title=John Clive Ward|date=October 2000|volume=53|issue=10|pages=99–100|url=http://www.physicstoday.org/resource/1/phtoad/v53/i10/p99_s1?bypassSSO=1|doi=10.1063/1.1325207}}</ref>  This celebrated result, in [[quantum electrodynamics]], was inspired by a  conjecture of [[Freeman Dyson|Dyson]]<ref>F. J. Dyson, The S matrix in quantum electrodynamics, ''Phys. Rev.'' '''75''', 1736-1755 (1949).</ref> and was disclosed in a one-half page letter typical of Ward's succinct style.  In their recent book entitled ''Quantum Electrodynamics'', Greiner and Reinhardt state in their discussion of charge [[renormalization]]: "Yet the Ward Identity has a much more fundamental significance: ''it ensures the universality of the electromagnetic interaction''."<ref>W. Greiner and J, Reinhardt, ''Quantum Electrodynamics'', 4th Ed. (Springer, Berlin, 2009).</ref> 
 
In his book ''The Infinity Puzzle'', [[Frank Close]] devotes a whole chapter to this Ward creation and entitles it '''The Identity of John Ward''', in which he writes: "Ward Identities lie at the very foundations of renormalization."<ref name=TIP>F. Close, ''The Infinity Puzzle'' (Oxford University, Oxford, 2011).</ref>
 
[[Andrei Sakharov]] classified Ward as one of the "''titans''" of [[quantum electrodynamics]] alongside [[Freeman Dyson|Dyson]], [[Richard Feynman|Feynman]], [[Julian Schwinger|Schwinger]], and [[Sin-Itiro Tomonaga|Tomonaga]].<ref>A. Sakharov, ''Memoirs'' (Knopf, New York, 1990).</ref>  In this regard, it has been said that physicists have made use of his principles and developments "''often without knowing it, and generally without quoting him.''"<ref>M. Dunhill, Professor John Clive Ward, in ''The Merton Record'' (Oxford University, Oxford, 1995).</ref>
 
==Additional contributions==
 
===Ward's probability amplitude for quantum entanglement===
 
In a 1947 paper, published in ''[[Nature (journal)|Nature]]''<ref name=W1947>M. H. L. Pryce and J. C. Ward, Angular correlation effects with annihilation radiation, ''Nature'' '''160''', 435 (1947).</ref> (with Maurice Pryce), Ward was the first to calculate, and use, the probability amplitudes for the polarization of two [[Quantum entanglement|entangled]] photons moving in opposite directions.<ref name=D2012>F. J. Duarte, The origin of quantum entanglement experiments based on polarization measurements, ''Euro. Phys. J. H'' '''37''', 311-318 (2012).</ref>  For polarizations ''x'' and ''y'', Ward derived this probability amplitude to be<ref name=JCW1949>J. C. Ward, ''Some Properties of Elementary Particles'' (D. Phil. Thesis, Oxford University, 1949).</ref>
 
:<math>\left|\psi\right\rang=(\left|x,y\right\rang - \left|y,x\right\rang ) </math>
 
which once normalized can be expressed as<ref name=D2012/><ref>F. J. Duarte, ''Quantum Optics for Engineers'' (CRC, New York, 2013) Chapter 17.</ref>
 
:<math>\left|\psi\right\rang= {1 \over \sqrt{2}}(\left|x\right\rang_{1} \left|y\right\rang_{2}- \left|y\right\rang_{1} \left|x\right\rang_{2}) </math>
 
where 1 and 2 refer to the two quanta propagating in different directions.  Ward's probability amplitude is then applied to derive the correlation of the quantum polarizations of the two photons propagating in opposite directions.<ref name=W1947/> This prediction was experimentally confirmed by [[Chien-Shiung Wu|Wu]] and Shaknov in 1950.<ref>C. S. Wu and I. Shaknov, The angular correlation of scattered annihilation radiation, ''Phys. Rev.'' '''77''', 136 (1950).</ref> In current terminology this result corresponds to a pair of entangled photons and is directly relevant to a typical [[EPR paradox|Einstein-Podolsky-Rosen (EPR) paradox]], or situation, as explained by [[Richard Dalitz|Dalitz]] and [[F. J. Duarte|Duarte]].<ref name=D2012/><ref name=pt1>[[Richard Dalitz|R. H. Dalitz]] and [[F. J. Duarte]], John Clive Ward, ''Physics Today''  '''53''' (10), 99-100 (2000).</ref>
 
===Quantum statistics, Fermion theory, the Ising Model, Feynman diagrams, and Aldermaston===
 
In addition, he made important contributions to [[quantum mechanics]],<ref name=JCW1949 /><ref>[[Elliott Waters Montroll|E. W. Montroll]] and J. C. Ward, Quantum statistics of interacting particles; general theory and some remarks on properties of an electron gas, ''Phys. Fluids'' '''1''', 55-72 (1958).</ref> fermion theory,<ref>[[Joaquin Mazdak Luttinger|J. M. Luttinger]] and J. C. Ward, Ground-state energy and many-fermion system, ''Phys. Rev.'' '''118''', 1417-1427 (1960).</ref> quantum [[solid-state physics]],<ref>J. C. Ward and J. Wilks, Second sound and the thermo-mechanical effect, ''Phil. Mag.'' '''43''', 48-50 (1952).</ref> and [[statistical mechanics]] and the [[Ising model]].<ref name=KW1952>[[Mark Kac|M. Kac]] and J. C. Ward, A combinatorial solution of the two-dimensional Ising model, ''Phys. Rev.'' '''88''', 1332-1337 (1952).</ref><ref>R. B. Potts and J. C. Ward, The combinatorial method and the two-dimensional Ising model, ''Prog. Theor. Phys.'' '''13''', 38-46 (1955).</ref><ref>E. W. Montroll, R. B. Potts, and J. C. Ward, Correlations and spontaneous magnetization of the two-dimensional Ising model, ''J. Math. Phys.'' '''4''', 308-322 (1963).</ref>  His joint work, with Kac, on the Ising Model<ref name=KW1952 /> gave rise to what is now being called the Kac-Ward operator.<ref>L. O. Chekhov, A spectral problem on graphs and L-functions, ''Russian Math. Surv.'' '''54''', 1197 (1999).</ref>
He is further credited with being an early pioneer in the use of [[Feynman diagrams]].<ref>D. Kaiser, ''Drawing Theories Apart: The Dispersion of Feynman Diagrams in Postwar Physics'' (University of Chicago, Chicago, 2005).</ref> 
 
In 1955-1956 Ward worked, at Aldermaston, on British [[atomic weapon]]s and has been portrayed as the "creator of the British [[hydrogen bomb]]".<ref>J. V. Malheiros, ''Publico'' (Lisbon, 4 April 1992) pp. 2-6 in Portuguese.</ref>  This topic is discussed by historian [[Lorna Arnold]]<ref>L. Arnold, ''Britain and the H-Bomb'' (Palgrave, New York, 2001).</ref> while Ward's own account is given in his memoirs.<ref>J. C. Ward, ''Memoirs of a Theoretical Physicist'' (Optics Journal, Rochester, New York, 2004) Chapter 8.</ref>  An additional analysis on this issue is provided by one of Ward's colleagues, and friend, [[Richard Dalitz]], who wrote:  "Ward had independently conceived a two-stage device".<ref name=pt1 />
 
===Standard Model===
 
Ward is also one of the authors of the [[Standard Model]] of gauge particle interactions: his contributions were published in a series of papers he co-authored with [[Abdus Salam]].<ref>A. Salam and J. C. Ward, Weak and electromagnetic interactions, ''Nuovo Cimento'' '''11''', 568-577 (1959).</ref><ref>A. Salam and J. C. Ward, On a gauge theory of elementary interactions, ''Nuovo Cimento'' '''19''', 166-170 (1961).</ref><ref>A. Salam and J. C. Ward, Electromagnetic and weak interactions, ''Phys. Lett.'' '''13''', 168-171 (1964).</ref><ref>A. Salam and J. C. Ward, Gauge theory of elementary interactions, ''Phys. Rev.'' '''136 B''', 763-768 (1964).</ref> An insightful and well documented discussion on Ward's contribution to the physics of the Standard Model is given by Gordon Fraser in the book ''Cosmic Anger''.<ref>G. Fraser, ''Cosmic Anger'' (Oxford University, Oxford, 2008).</ref>  This topic is discussed further by [[Frank Close]], who provides an illuminating perspective on the importance of Ward's contribution to the Standard Model.<ref name=TIP />
 
[[F. J. Duarte|Frank Duarte]] writes about a series of conversations with [[Richard Dalitz]] who conveyed that, following his own careful scrutiny, Ward's contribution to the Standard Model was "more extensive than accepted by popular belief."<ref name=LP2012>[http://www.opticsjournal.com/laserphysicist.htm F. J. Duarte, ''Laser Physicist'' (Optics Journal, New York, 2012)].</ref> Duarte adds that albeit Ward initially expressed "annoyance" at his exclusion from the 1979 Nobel, he later "projected a fairly serene attitude towards this topic and even joked about the existence of more lucrative prizes."<ref name=LP2012 /> Ward's own account is provided in his memoirs, in his usual laconic style.<ref>J. C. Ward, ''Memoirs of a Theoretical Physicist'' (Optics Journal, Rochester, New York, 2004) Chapters 4 and 9.</ref>   
 
The contributions of Salam and Ward to the Standard Model were crucial to the development of the theoretical structure of the [[Higgs boson]], as described by [[Peter Higgs|Higgs]] himself.<ref>[[Peter Higgs|P. W. Higgs]], Spontaneous symmetry breakdown without massless bosons, ''Phys. Rev.'' '''145''', 1156-1163 (1966).</ref>
 
==Macquarie University==
 
After [[World War II]], Ward worked in several places in the [[United States]] and eventually he moved to [[Sydney, Australia]], via [[New Zealand]].<ref name=pt1 />  In 1964 he created the physics program of [[Macquarie University]] using the [[Feynman Lectures on Physics]] as primary textbooks.  This program had a strong experimental emphasis and Ward himself (who originally was trained as an engineer) "had great admiration for anything practical".<ref name=AP2009>[http://www.opticsjournal.com/AUSTRALIAN%20PHYSICS%2046%286%29%20171-175%20%282009%29.pdf F. J. Duarte, The man behind an identity in quantum electrodynamics, ''Australian Physics'' '''46''' (6), 171-175 (2009)].</ref> Also, Ward regarded physics as a ''vocation'' rather than a profession.<ref name=LP2012 />
 
In the late 1970s Ward participated, with [[F. J. Duarte|Frank Duarte]], in the successful [[Macquarie science reform movement]].<ref>B. Mansfield and M. Hutchinson, ''Liberality of Opportunity: A history of Macquarie University 1964-1989'' (Hale and Iremonger, Sydney, 1992).</ref><ref>J. C. Ward, ''Memoirs of a Theoretical Physicist'' (Optics Journal, Rochester, New York, 2004) Chapter 13.</ref> and considered this a "most important  accomplishment".<ref name=AP2009/>
 
==Personal==
 
Ward's total number of published papers was only about 20, a fact that reflects a strong sense of self-criticism.  He was also critical of what he called "PhD factories" and expressed skepticism towards the importance being attached to large number of citations.  Ward's "directness and frankness often got him at odds with managers and administrators."<ref name=LP2012/>
 
Besides his physics, Ward was an accomplished pianist and French horn player.  Although a bachelor most of his life, he was briefly married while in the US. In Sydney, he lived at 10 Fern Street, in the northern suburb of [[Pymble]].<ref name=LP2012/> He has an [[List of people by Erdős number|Erdős number]] of 2.
 
===After death===
 
In immediate correspondence following his death, [[Willis E. Lamb]] wrote "I greatly admired him and his work... I hope our paths cross again."  [[Philip Warren Anderson|Philip Anderson]] highlighted Ward's contribution to the [[Standard Model]] while indicating that he had communicated his passing to [[Freeman Dyson]].<ref name=LP2012 /> Ward's succinct unfinished memoirs were published in 2004.<ref>J. C. Ward, ''Memoirs of a Theoretical Physicist'' (Optics Journal, Rochester, New York, 2004).</ref>
 
==Ward's friends and co-authors==
[[Image:Fermi Surface.svg|thumb|200 px|right|[[Luttinger's theorem]] (introduced by J. M. Luttinger and J. C. Ward) relates a Fermi liquid's particle density to the volume of its Fermi surface.]]
*[[Ronald Ernest Aitchison]]
*[[Richard Dalitz]]
*[[F. J. Duarte]]
*[[M. Kac]]
*[[Willis E. Lamb]]
*[[J. M. Luttinger]]
*[[R. E. B. Makinson]]
*[[Elliott Waters Montroll]]
*[[Jose Enrique Moyal]]
*[[James A. Piper]]
*[[Renfrey Potts|R. B. Potts]]
*[[Maurice Pryce|Maurice H. L. Pryce]]
*[[A. W. Pryor|Arthur W. Pryor]]
*[[Abdus Salam]]
 
==See also==
[[Image:vertex correction.svg|thumb|200 px|right|The one-loop correction to the [[vertex function]]. This is the dominant contribution to the anomalous magnetic moment of the electron.]]
 
*[[Feynman diagrams]]
*[[Gauge fixing]]
*[[Gauge theory]]
*[[Ising model]]
*[[Luttinger's theorem]]
*[[Noether's theorem]]
*[[Path integral formulation]] (of quantum mechanics).
*[[Quantum electrodynamics]]
*[[Quantum entanglement]]
*[[Renormalization]]
*[[Standard model]]
*[[Vacuum polarization]]
*[[Vertex function]]
*[[Ward–Takahashi identity]] (Includes a brief description of the Ward Identity).
 
==References==
{{reflist|2}}
 
==External links==
 
{{wikiquote}}
*[http://www.opticsjournal.com/JCWard.pdf Unfinished autobiography: J. C. Ward, ''Memoirs of a Theoretical Physicist'' (Optics Journal, Rochester, New York, 2004.] (online).
*[http://www.opticsjournal.com/ward.htm Biographical note] (includes Ward's publications and picture).
*[http://ptonline.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=PHTOAD000053000010000099000001&idtype=cvips AIP biography] ([[Richard Dalitz|R. H. Dalitz]] and [[F. J. Duarte]], ''Physics Today'' '''53''' (10), 99–100 (2000)).
 
{{Persondata <!-- Metadata: see [[Wikipedia:Persondata]]. -->
| NAME              =Ward, John Clive
| ALTERNATIVE NAMES =
| SHORT DESCRIPTION = British-Australian nuclear physicist
| DATE OF BIRTH    =1 August 1924
| PLACE OF BIRTH    =[[London]], [[England]]
| DATE OF DEATH    =6 May 2000
| PLACE OF DEATH    =[[Vancouver]], [[Canada]]
}}
{{DEFAULTSORT:Ward, John Clive}}
[[Category:1924 births]]
[[Category:2000 deaths]]
[[Category:Australian physicists]]
[[Category:English physicists]]
[[Category:British physicists]]
[[Category:Australian nuclear physicists]]
[[Category:British nuclear physicists]]
[[Category:Particle physicists]]
[[Category:Quantum physicists]]
[[Category:Theoretical physicists]]
[[Category:Optical physicists]]
[[Category:Fellows of the Royal Society]]
[[Category:Fellows of the Australian Institute of Physics]]
[[Category:Macquarie University faculty]]
[[Category:Paul Erdős]]

Latest revision as of 13:06, 5 December 2014

Hi there. Allow me begin by introducing the author, her name is Myrtle Cleary. For a while she's been in South Dakota. Managing individuals is his occupation. The preferred hobby for my kids and me is to perform baseball and I'm trying to make it a occupation.

My web site - Theoffshoremanual.com