Its name is Quantum Cloud. Visitors to Lon-don cannot miss it when visiting the parknext to the Millennium Dome or taking acruise along the Thames. It rises 30 m abovea platform on the banks of the river, andfrom a distance looks like a huge pile of steelwool. As you draw closer, you can make outthe hazy, ghost-like shape of a human beingin its centre. It is a sculpture, by the Britishartist Anthony Gormley, made from steelrods about a metre and a half long that areattached to each other in seemingly hap-hazard ways. Framed by the habitually greyLondon sky, it does indeed look cloud-like.But “quantum”?

The word quantum has a familiar and well-documented scientific history. Max Planckintroduced it into modern discourse in 1900

to describe how light is absorbed and emit-ted by black bodies. Such bodies seemed todo so only at specific energies equal to mul-tiples of the product of a particular frequencyand a number called h, which he called aquantum, the Latin for “how much”. Planckand others assumed that this odd, non-Newtonian idea would soon be replaced bya better explanation of the behaviour of light.

No such luck. Instead, quantum’s pres-ence in science grew. Einstein showed thatlight acted as if it were “grainy”, while Bohrincorporated the quantum into his accountof how atomic electrons made unpredictableleaps from one state to another. The quan-tum began cropping up in different areas ofphysics, then in chemistry and other sciences.A fully fleshed out theory, called quantummechanics, was developed by 1927.

Less familiar and well documented,though, is quantum’s cultural history. Soonafter 1927 the word, and affiliated terms such as “complementarity” and “uncertaintyprinciple”, began appearing in academicdisciplines outside the sciences. Even thefounders of quantum mechanics, includingBohr and Heisenberg, applied such terms tojustice, free will and love. Quantum has made

unpredictable leaps to unexpected placesever since. The next James Bond film, for ex-ample, is to be called Quantum of Solace.

The quantum momentThe dean of my university at Stony Brook,James Staros, who is a scientist, sometimesrefers to his faculty as being “quantized”.When budgets need to be cut, for example,he points out that it is impossible to reduceone department by, say, 0.79 positions andanother by 1.21 positions, even if those num-bers are perfectly proportionate to the cut.As Staros explains, “it has to be one fromeach, even if the departments are somewhatdifferent in size”. This is a precise and effect-ive rhetorical use of quantum language.

And when I asked Gormley about hissculpture’s name, he gave me a cogent re-sponse. “The development of quantum me-chanics,” he told me, “represents the shift in science from the study of even more dis-crete entities to increasing attention to flowand field phenomena in which emergentforms are seen as evolving out of their con-texts. Quantum Cloud evokes this.”

While both Gormley and Staros deployquantum language in a fairly precise fashion,

Critical Point Quantum of culture

Terminology from quantumtheory shows up frequently inpopular culture – from art andfilms to sculpture and poetry.Robert P Crease asks for yourfavourite examples

Emergent form

Anthony Gormley’s

Quantum Cloud rising

above the Thames

in London.

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19Physics World September 2008

on other occasions it is badly abused, bring-ing to mind James Clerk Maxwell’s ob-servation that “the most absurd opinionsmay become current, provided they are ex-pressed in language, the sound of which re-calls some well-known scientific phrase”.The word quantum, for instance, appearsregularly in pseudoscience, self-help andquack-medicine discourse.

Yet if we think scientifically rather thanjudgmentally, all uses of quantum language– whether precise or pretentious, technicallycorrect or ill-informed and designed to im-press – are interesting. After all, each is moti-vated by some conception of the meaning of the quantum. But what patterns can wefind in those conceptions? And what dothese patterns say about culture and how itunderstands science?

My colleague Fred Goldhaber and I haveraised these questions in a course called“The quantum moment”, which we havegiven several times to students at StonyBrook. We stole the name from MordecaiFeingold’s book The Newtonian Moment:Isaac Newton and the Making of ModernCulture, which sprang from an exhibition atthe New York Public Library in 2004–5 thatexamined Newton’s impact on the cultureof the late 17th and early 18th century. In asimilar vein, Goldhaber and I were keen togauge what impact the word quantum hashad on today’s culture.

We discovered that the answer is compli-cated, for quantum has spread across theworld in various ways.

Pattern #1: irreducibly statistical processesOne pattern involves applying quantumterms to irreducibly statistical processes. Forabout a quarter of a century, physicists have

applied mathematical constructs developedfor quantum phenomena to economics. Forexample, in his book Quantum Finance: PathIntegrals and Hamiltonians for Options andInterest Rates, physicist Belal Baaquie of the National University of Singapore notesthat he is not applying quantum theory itselfto finance. “Instead,” he writes, “the term‘quantum’ refers to the abstract mathe-matical constructs of quantum theory thatinclude probability theory, state space, oper-ators, Hamiltonians, commutation equa-tions, Lagrangians, path integrals, quantizedfields, bosons, fermions, and so on. All thesetheoretical structures find natural and use-ful applications in finance.” The word quan-tum here refers not to quantization as such, but to the application of its statisticalmethods to stochastic processes such as in-terest rates and stock-price fluctuations.

For something completely different, con-sider Quantum Sheep, the brainchild ofValerie Laws, a writer who lives in the northof England. In 2002 she spray-painted wordsonto the fleeces of sheep from a nearby farm.As the flock milled about, the words re-arranged and a new “poem” was createdevery time the sheep came to rest. A spokes-person for Northern Arts, which provided£2000 of funding for the project, said that theresult was “an exciting fusion of poetry andquantum physics”. Here is one of the result-ing “Haik-Ewes”:

Clouds graze the skyBelow, sheep drift gentleOver fields, soft mirrorsWarm white snowTalking to the BBC at the time, Laws

explained why she felt the project was worthpursuing. “Randomness and uncertainty is at the centre of how the universe is put

together, and is quite difficult for us ashumans who rely on order,” she said. “So Idecided to explore randomness and some of the principles of quantum mechanics,through poetry, using the medium of sheep.”

There is, of course, a world of differencebetween calculating interest rates and set-ting a herd of painted sheep loose in thecountryside. But both of these cases weremotivated by the role of randomness inquantum theory: the former case involves an actual use of its statistical methods, whilethe latter invokes quantum as a symbol ofirreducibly random processes.

Pattern #2: complementary beerQuantum Man is a sculpture by Julian Voss-Andreae currently installed in the City ofMoses Lake, Washington (Physics WorldSeptember 2006 p7). Made of steel sheets2.5 m high that lie parallel to each other, thesculpture changes in form as you walkaround it. From one perspective it revealsthe outline of a human being, while fromanother the human form disappears entirely.

The sculpture, says the artist, is “a me-taphor for the counterintuitive world ofquantum physics”. Voss-Andreae shouldknow. He studied physics as an undergradu-ate in Berlin and Edinburgh, and did gradu-ate research in Vienna with Anton Zeilingeron the double-slit experiments involving thequantum interference of carbon-60 bucky-ball molecules (Physics World November2006 p44).

The metaphor is thus grounded in com-plementarity, Bohr’s name for the fact that,in the quantum world, two features of adescription can be necessary but mutuallyexclusive – a particle having a definite posi-tion and momentum being the standard ex-ample. However, Bohr and several otherleading physicists of the time felt that com-plementarity could also be extended to areasother than physics, an idea that has oftenbeen ridiculed. Yet after reviewing some ofBohr’s applications of complementarity tothe social world, one of Bohr’s biographers,the hard-nosed physicist Abraham Pais,found that while such applications wereclearly metaphorical, they often helped himthink “outside the box”. Pais declared that“Personally, I have found the complement-ary way of thinking liberating.”

I do not know how liberating Pais wouldhave found the psychotherapist LawrenceLeShan’s more fanciful defence of mysticismin his book The Medium, the Mystic, and thePhysicist. Mystics seek the comprehension ofa different view of reality, LeShan wrote,before adding that “I use the term ‘compre-hension’ here to indicate an emotional aswell as an intellectual understanding of andparticipation in this view…In physics this iscalled the principle of complementarity. Itstates that for the fullest understanding ofsome phenomena we must approach themfrom two different viewpoints. Each view-

Now ewe see it? These spray-painted sheep helped Valerie Laws create the poems Quantum Sheep.

JK

Pre

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20 Physics World September 2008

point by itself tells only half the truth.”And while quantum terminology can

be well grounded or fanciful, it can also besimply tongue-in-cheek. Take, for example,the Quantum Beer Theory website (wohlmut.com/beer) created by Kyle Wohlmut, a trans-lator and dedicated beer fanatic who lives in the Netherlands. Wohlmut, who last stud-ied physics in high school, explains thatunderlying his theory is the fact that “theessential experience of beer flavour arisesfrom conflict”. In each beer, he claims, twosides of taste – hops and malt – struggle forsupremacy. “These two sides wage a war todominate your palate,” he says, “and the bestbeers happen when the two sides becomeentrenched in defensible positions, pro-tracting the battle into epic proportions.”

When I asked why Wohlmut uses theword “quantum”, he explained to me that it was to underscore the “level of serious-ness” that he feels ought to be attached tothe analysis of beer. Another reason is that,despite his best efforts, he has found it al-most impossible to make home-brewed beerconsistent in taste and quality – forcing himto conclude that some mysterious, unknownfactors in beer production must be oper-ating at the quantum scale.

I am sure that Pais, who liked a good laugh,would drink to that.

Pattern #3: by leaps and BondsAnother interesting use of the word quantumappears in Ian Fleming’s story Quantum ofSolace, which first appeared in Cosmopolitanmagazine in 1959 and was reprinted in hiscollection For Your Eyes Only. It is not a spythriller, but a serious short story that he wrotewhile his marriage was failing. The maincharacter, the governor of Nassau, tells Bond

late one night in the course of a heart-wrenching story that human relationships cansurvive even the worst disasters if both part-ners retain at least a certain amount of hu-manity. When partners stop caring, and “thequantum of solace stands at zero”, then thepain can not only end the relationship, butalso cause the partners to destroy each other.

Fleming’s use of the word “quantum” isclose to Planck’s and to the original Latin: it means a finite amount of some quantity.However, the upcoming movie is said toshare nothing but the title with the originalstory, which begs the question: exactly whatdoes the word refer to in the title of the film?I guess we will all have to wait until Novem-ber when the film is officially released.

The critical pointThese are only three of the patterns thatGoldhaber and I found. There are others,involving such things as acausality, nonlocal-ity and cats, but there must be more besides.So what manifestations of quantum languagehave you spotted in popular culture? Whatpatterns do these reveal? And what do thesepatterns reveal about the social world? Letme know your thoughts and I shall devote afuture column to the responses.

Robert P Crease is chairman of the Department

of Philosophy, Stony Brook University, and historian

at the Brookhaven National Laboratory, US,

e-mail rcrease@notes.cc.sunysb.edu

● What are your favourite examples of quan-tum, and its affiliated ideas such as comple-mentarity and the uncertainty principle, inpopular culture? What patterns do these re-veal? E-mail your contributions to Robert PCrease at rcrease@notes.cc.sunysb.edu

Different perspectives The Quantum Man sculpture by former physicist Julian-Voss Andreae.

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21Physics World September 2008