EMILIO SEGRÈ VISUAL ARCHIVES/AM. INST. PHYS./SPL P Nobel winnerwhotransformed condensed-matter andparticlephysics. pathologist, he grew up in Urbana–Champaign, able parallel between magnetism and in antiferromagnetism. and accounted for the interactions that result explained how iron atoms become magnetic, repulsion Anderson andquantum mechanics, layers. Bycombining the effects of electron spin alternates direction onadjacent atomic drives rely onan antiferromagnet, inwhichthe tion. Bycontrast, theread headsof hard disk results whenspinsorientinthesamedirec called spin.Theattraction of fridge magnets tiny magneticmoments that electrons carry predictson magnetism.Quantummechanics Hill, NewJersey. Here, focused Andersonfirst group atBellTelephone Laboratories inMurray transistor, hired Anderson to join the theory of those withwhomheshared theNobelprize. mentored by John Hasbrouck Van Vleck, one pressure onthebroadening of spectral lines, for graduate work, hestudied theeffects of repay loan. Returning awartime to Harvard a colleague gave himaprecious text onitto learntfirst about quantum when mechanics Research inWashington Laboratory DC.He World War, heworked onradar attheUSNaval he fell inlove withphysics. During theSecond versity inCambridge, Massachusetts, where speed skating. At 16, hewent to Harvard Uni Illinois, anddeveloped anearlypassion for science andeconomics. physics,necting chemistry, biology, computer level of complexity requires con newfields, icant. Hereasoned that,inscience, eachnew when matter comes together are equallysignif ing thattheemergent properties thatdevelop Andersonrejectedparticles. thisview, argu from reducing nature to itsmost fundamental some that advances would derive exclusively part of thestandard modelof particlephysics. mass: theAnderson–Higgs mechanismisnow subatomic such particles, asphotons, acquire him to propose how theforce carriersbetween netism. His studies of superconductors led tors, and for his pioneering work on mag whereby disordered metalsbecome insula (1923–2020) Philip W. Anderson Obituary In 1958, Andersondiscovered aremark In 1949, WilliamShockley, co-inventor of the Anderson was bornin 1923. The son of a plant Quantum physics’ earlytriumphspersuaded aged 96, ledthedevelopment of con- his discovery of electron localization, a share of the Nobel Prize in Physics for densed-matter physics. In1977, hewon hilip Warren Anderson, whohasdied ------deeper parallels between superconductivity he foundthatthey acquired amass. motion of photons inside a superconductor, by photons. WhenAndersoncalculated the the electromagnetic which are fields, carried cause an current electric that interacts with pairs are charged, andpseudospin waves tion propagate, formingaspinwave. Cooper In amagnet,fluctuations inthemagnetiza ized thatthese pairs are akindof pseudospin. electrons forming Cooper pairs, Anderson real discovery that superconductivity results from Bardeen, Leon Cooper andRobert Schrieffer’s allowing themto levitate. Following John centrate superconductors fields, expel them, developed indetail.Andersonalsostudied spin contributions of many leading physicists to be idea was radical and took two decades and the of waves indisordered media.Buttheoriginal is recognized asageneral property of allkinds ing an insulator. Today, Anderson localization a material —localizes electron waves, produc- such as that caused by defects and impurities in Anderson to propose in1957 thatdisorder — of theHiggs boson. Higgs’s 1964 paper predicting theexistence Anderson’s work was prominently cited in afterfield theBritishphysicist Peter Higgs. mic superconductor, now known astheHiggs gauge bosons to acquire mass inakindof cos- mechanism forsubatomic force carrierscalled and particle physics. In1962, heproposed a superconductivity. Whereas magnets con © Anderson realized thatthere were still- Work onsemiconductors atBellLabsled
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A l l r i g h t s r e s e r v e d . - - - interpretation, andworked closely with could instinctively see several moves beyond master in the ancient game of Go. Just as he Kubo at the University of Tokyo, he became a 1953, visitingthemathematicalphysicist Ryogo of study.new fields Duringayear inJapan in experimentalists to develop ideasthatledto used inmodernmachinelearning. was anearlyforerunner of theneural networks environment. The Edwards–Anderson model glass’s capacity to ‘remember’ of its the history University of Cambridge, UK,hemodelledthe interactions. Working Edwards withSam atthe both ferromagnetic andantiferromagnetic glasses, atypeof random magnetthatcontains e-mail: [email protected] Anderson at Princeton in 1980–1984. He was a graduate student with Philip W. Rutgers, University the State of New Jersey. at the Rutgers Center for Materials Theory, Piers Coleman is a distinguished professor us, hisideasare still many moves ahead. of how it might be. Although Anderson has left many thinkthatRVB contains theseeds theory conductivity hasstill notbeenachieved, but quantum spinliquid.High-temperature super from of theinjection charge into aninsulating high- rows ideas from magnetism, positing that theory, proposed in1987, once again bor 1986 by Georg BednorzandAlex Müller). temperature superconductivity (discovered in where hedevoted muchof hisresearch to high- tion atPrinceton University inNewJersey, Nobel prizewinners. In1975, hetook upaposi- associate of Nevill Mott,thethird of the1977 professor at Cambridge, where he was a close his house. gardening and clearingthewoodland around a passion fortheoutdoors, spendingSundays dinner, developing lasting friendships.Hehad He would invite them,and theirfamilies,for inspiring ideas,hewas somethingof aguru. tored, withwhomhegenerously shared mathematics. lems so they would succumb to aminimum of physicist, hewas able to reduce complex prob to grasp. Unusually intuitive foratheoretical standing of physics thatwas hard forothers his opponent,heoften reached anunder Anderson hadanartist’s eye fororiginal Anderson’s resonating valence bond(RVB) From 1967 to 1975, Andersonwas avisiting To themany younger physicists hemen temperature superconductivity results Nature |Vol 581 |7 May 2020 |29
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