Category Archives: History, sociology, and philosophy

The future of computational science—in 1977

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CharlesEchoClash-275 In the spring of 1977, Queen Elizabeth II toured New Zealand to celebrate the 25th anniversary of her reign, astronomers using the Kuiper Airborne Observatory discovered the rings of Uranus, and—of more significance to the 14-year-old me—the punk band the Clash released its eponymous first album.

That same spring, Philip Abelson, the last physicist to serve as Science’s editor in chief, devoted an entire issue of the magazine to what he called the electronics revolution. The issue’s timing was apt. Three of the earliest and most successful personal computers—the Apple II, Commodore International’s Personal Electronic Transactor (PET), and Tandy’s TRS-80—made their debuts in 1977. As Abelson recognized, advances in the design and manufacture of integrated circuits were propelling a revolution in the availability and capability of computers.

If you scan the table of contents of that issue, you’ll find a total of 27 articles. They covered such diverse topics as electronic mail, satellite communications, computing in banking and marketing, the future of integrated circuits, and software engineering. One article presciently addressed the use of electronic media in education.

Computational science was included, too. Seven members of the technical staff at Bell Labs wrote an article entitled “Computers and research.” When I read the article for the first time this week, I was struck by how much William Baker and his coauthors got right. Not knowing how computational power would evolve, they took a broad, imaginative view of how computers would benefit research—and not just in crunching numbers.

The Bell Labs group predicted the positive impact of computers on scientific publishing. They also recognized the importance of computer science in its theoretical aspect (to elucidate the scope of what problems can be solved computationally) and in its practical aspect (to develop new computer languages).

But what most impressed me about the article was the observation that computers would change the ideas that scientists would come up with:

Broadly, these are now more complex ideas about more complex matters. But a complicated idea is worthless unless something can be done about it. What has changed is the usable level of idea complexity. Computers have significantly expanded the domain of tractable complexity.

By tractable complexity, Baker and his coauthors didn’t simply mean a bigger calculation with more mathematical terms. Rather, they anticipated the use of computers in such messily intricate fields as ecology, psychology, and economics. Now, the frontiers of tractable complexity include topics such as climate change, strongly correlated electron systems, and cell metabolism.

Besides bringing evermore complex problems into the realm of the tractable, where does the future of computers and research lie? Given the increasing sophistication of 3D printing, I foresee that computers will be used not only to design and analyze experiments, as they are today, but also to direct experiments’ assembly and performance.

To see what I mean, imagine a spacecraft touching down on the surface of an icy extrasolar planet that lies far beyond the range of practical back-and-forth telecommunication. Once the spacecraft’s drill has broken through the ice, sensor-equipped tentacles unfurl in the water below to evaluate the conditions. Based on the sensor data, the onboard computer equips its fleet of robot submarines with the appropriate mix of sensors designed to maximize the success of its mission: finding life.

This essay by Charles Day first appeared on page 104 of the May/June 2012 issue of Computing in Science & Engineering, a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society:

Scenes from Married Life: A novel by a physicist about a physicist

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I’ve just finished reading two novels by William Cooper, the pen name of Harry Hoff. Born in Northern England in 1910, Cooper studied physics at Cambridge University, where his academic adviser was physicist, novelist, and bureaucrat C. P. Snow.

Cooper’s first job after earning his bachelor’s degree was as a high school physics teacher in Leicester, a modestly sized city in England’s East Midlands. His 1950 novel Scenes from Provincial Life is set in such a city just before World War II and follows the life of Joe Lunn, a physics teacher who aspires to be a successful novelist.

Although it’s not well known, Scenes from Provincial Life was the first of several novels of the 1950s whose protagonists’ ordinary lives illuminated with wry humor the smug, dreary conventions of contemporary Britain. John Wain’s Hurry On Down (1953), Kingsley Amis’s Lucky Jim (1954), and Keith Waterhouse’s Billy Liar (1959) were among the novel’s progeny.

Cooper doesn't name the city in which Scenes from Provincial Life takes place, but his description of an ornate clock tower strongly suggests Leicester, the city where he taught physics in the 1930s.

Cooper doesn’t name the city in which Scenes from Provincial Life takes place, but his description of an ornate clock tower strongly suggests Leicester, the city where he taught physics in the 1930s.

Cooper’s novel attracted me not just because of its literary importance. I was also intrigued to see if his background as a physicist was manifest in the novel’s characters, plot, or themes. It wasn’t. Besides one brief episode in which Lunn tells his senior class to look for Newton’s rings, little of physics or physicists makes an appearance. Lunn, perhaps like Cooper himself, was more preoccupied with writing and sex.

The edition I bought paired Scenes from Provincial Life with one of its sequels, Scenes from Married Life. Set in London in 1950 and published in 1961, the novel continues to follow Lunn, who still writes novels, but who is now a civil servant tasked with ensuring that Britain’s research enterprise has the scientific staff it needs to flourish.

Cooper’s mentor, Snow, appears in the novel as Lunn’s boss, Robert (we never learn his surname). Together, the two physicists engage in office politics and pursue their respective literary careers. They also each meet and marry teachers.

As in the earlier novel, physics remains in the background. But there are at least two episodes in which Cooper’s inner physicist speaks out. The first is rather brief. Shopping for rings with Robert, Lunn is shocked to discover that wedding rings are much cheaper than engagement rings. “I had no idea the wedding rings were to be had for units of pounds,” he writes as any physicist might.

The second episode is longer and launches one of the novel’s subplots. Lunn is assigned to interview organic chemists for temporary jobs at one of Britain’s explosives research establishments. Evidently, Lunn (and presumably his creator too) held a low opinion of organic chemists, as you can tell from the following extract:

Organic chemists had come to be my bêtes noires—they seemed to me to be characterized by a peculiar combination of narrowness and complacency, having changed neither their techniques nor their opinion of themselves since the days of World War I. Organic chemistry had seen some truly glorious days at the beginning of the century, and the 1914–18 war, with everybody thinking mostly about explosives and poison gas, had been a chemists’ war. But after that had come the glorious days of atomic physics; and World War II, with everybody thinking about first radar and then atomic bombs, was a physicists’ war. To the sort of young men I had to see the point had not gone home. On they went, sticking together parts of molecules, by their crossword-puzzley techniques, to make big molecules: then, by more crossword-puzzley techniques, they verified that they had made what they thought they had made: and then started all over again.

When asked if they used techniques nowadays invented and used by physicists, they said to me rebukefully:

“I rely on classical methods.”

And when invited to discuss the way their parts of molecules behaved in terms of electronic structure, they said very rebukefully indeed:

“I’m afraid I’m not a theoretician.”

Some of them, it seemed to me when I got particularly desperate, might never have heard the electron had been discovered.

(In fairness I have to say that since then—I am writing about 1951 and it is now 1960—my opinion has changed. Young organic chemists have changed, to the extent of whipping at least one “modern technique,” nuclear magnetic resonance, smartly out of the hands of physicists.)

Parenthetical caveat aside, the typical—even stereotypical—haughtiness of physicists with regard to the practitioners of other sciences shines out of the extract. In the novel, Lunn’s attitude to one organic chemist in particular leads to an incident that almost ends his career. I won’t say more, lest you want to read the novel for yourself.

As for Cooper, managing scientific workforces became his specialty. He worked at the UK Atomic Energy Authority to stem Britain’s brain drain and served as a personnel consultant to the European Commission. Like Lunn, he continued to publish books, although only Scenes from Provincial Life and Scenes from Married Life remain in print today.

Cooper died in 2002.

Let the public name exoplanets

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The names of the five stars closest to the Sun exemplify how confusing (or historically rich) astronomical nomenclature can be.

Proxima Centauri is the closest star. The second and third closest form a binary and are known collectively as α Centauri (or Rigel Kentaurus) and individually as α Centauri A and α Centauri B. The fourth closest is Barnard’s Star. The fifth is WISE 1049−5319, which is also known as Luhman 16.

The brown dwarf binary WISE 1049−5319 appears as a yellow disk in the center of this mid-wavelength IR image. CREDIT: NASA/IPAC Infrared Science Archive

The brown dwarf binary WISE 1049−5319 appears as a yellow disk in the center of this mid-wavelength IR image. CREDIT: NASA/IPAC Infrared Science Archive

Just how the five stars got their names depends, in part, on when they were first observed. Alpha Centauri is the third brightest star in the night sky. As such, it has been named by several cultures. Its Chinese name, 南門 (Nán Mén), means “Southern Gate.” Arab astronomers called it جل القنطورس (Rijl Qanṭūris), “Centaur’s Foot.”

The name α Centauri originates in the first systematic stellar naming convention, which was devised in 1603 by the Bavarian astronomer Johann Bayer. “Centauri” (“of Centaurus”) indicates the constellation that the star belongs to; the Greek letter indicates the star’s brightness rank in the constellation.

The other stars in the top five are not visible to the naked eye and weren’t, therefore, cataloged by Bayer, whose naming convention predated the invention of the telescope by eight years. Proxima Centauri and Barnard’s Star are both red dwarfs. Proxima was named by the astronomer who discovered it in 1915, Robert Innes. Barnard’s Star was named after Edward Barnard, who was the first to measure the star’s velocity across the sky in 1916.

Remarkably, the discovery of WISE 1049−5319 was published on arXiv just last month. Kevin Luhman of Penn State University and his collaborators identified the star—which is, in fact, a brown dwarf binary—in observations made by NASA’s Wide-field Infrared Survey Explorer spacecraft. The numbers after the spacecraft’s abbreviated name are the binary’s celestial coordinates.

Names like WISE 1049−5319 are now the norm in astronomy. Space-based and ground-based observatories whose sensitivity exceeds their predecessors tend to find many new objects. Although you can’t tell from its name that WISE 1049−5319 is a brown dwarf binary, you can presume from the WISE part of the name that it’s an IR source and that it’s faint (because if it were bright, it would have been discovered and named earlier). Using the coordinates to identify sources might seem long-winded compared to a serial number, but the coordinates are astronomically meaningful, whereas a serial number wouldn’t be.

Rakhat, α Centauri Bb, or both?

I was reminded of the quirkiness of astronomical names earlier this week, when I read a news story in New Scientist entitled “Closest exoplanet sparks international naming fight.”

The dispute pits Uwingu, a startup company whose mission is to fund projects that inform the public about space science, against the International Astronomical Union, the world’s official arbiter of astronomical naming conventions and planetary nomenclature for planetary bodies.

By IAU-sanctioned convention, exoplanets are named after the the stars they orbit, with the addition of a lower-case letter: “a” designates the star; “b,” the first planet discovered; “c,” the second; and so on. Officially, the closest exoplanet to the Sun is called α Centauri Bb, but if you paid Uwingu $4.99, you could suggest a name. And if you paid $0.99, you could vote on the suggestions. Currently, the leading name for α Centauri Bb is Rakhat, which is what Mary Doria Russell called a planet that orbits the star in her 1996 science fiction novel, The Sparrow.

I think it’s great that a real planet is named after a fictional one. Granted, Rakhat conveys less astronomical information than α Centauri Bb does, but I don’t see why the two names can’t coexist. I doubt anyone would be confused.

What’s more, the IAU’s exoplanet naming convention, though simple and straightforward, does not necessarily yield neat, rational names. That’s because the stars that harbor exoplanets, like the five stars closest to the Sun, follow a mix of naming conventions. Exoplanet examples include 51 Pegasi b (the first one discovered), KIC 12557548b (the evaporating exoplanet), and HD 85512 b (a super-Earth).

Despite astronomy’s modest technological payoffs, the general public continues to fund astronomical research—thanks, in part, to the time and energy astronomers devote to engaging the public. By giving people the opportunity to name exoplanets, Uwingu is making them partners in a scientific enterprise. The IAU should support, not fight, such deep public engagement.

Using statistics to catch cheats and criminals

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“If your experiment needs statistics, you ought to have done a better experiment,” Ernest Rutherford once declared. But when you work at the frontier of detection, as astronomers and particle physicists often do, you rely on statistical analysis to extract results. Indeed, if your experiment doesn’t need statistics, then you might be too far from the frontier to make an important discovery.

Despite such statistical triumphs as last year’s discovery of the Higgs boson, Rutherford’s disdain for—or at least suspicion of—statistics remains widespread. A recent statistical analysis demonstrated that visiting your doctor every year for a checkup doesn’t significantly prolong life. Of course, the practice doesn’t harm any individual patient, but its prevalence in the US raises the total cost of medical care, which harms society. Will the study make a difference? I doubt it.

Ernest Rutherford (1871–1937) and his coworkers discovered the atomic nucleus and the proton. They also performed the first experiments that transmuted one element into another. To learn more about Rutherford, visit the online exhibition Rutherford's Nuclear World. hosted by AIP's Center for the History of Physics.

Ernest Rutherford (1871–1937) and his coworkers discovered the atomic nucleus and the proton. They also performed the first experiments that transmuted one element into another. To learn more about Rutherford, visit the online exhibition Rutherford’s Nuclear World, which is hosted by AIP’s Center for the History of Physics. CREDIT: AIP Emilio Segrè Visual Archives (gift of Otto Hahn and Lawrence Badash)

I’m not sure what evidence would convince physicians to refrain from insisting on annual checkups, but they and anyone else who is skeptical of statistical analysis might be persuaded by a simmering scandal that boiled over recently in Atlanta, Georgia.

On 29 March the superintendent of the Atlanta school district, Beverly Hall, and 34 other educators were indicted in what a New York Times news story characterized as “the most widespread public school cheating scandal in memory.”

According to the indictment, the 35 educators conspired to raise students test scores by altering the tests after the students had taken them. Meeting in secret and wearing gloves to avoid leaving incriminating fingerprints, groups of teachers at various schools rubbed out wrong answers and replaced them with the correct ones.

Besides acclaim for appearing to fix badly performing schools, the conspirators also received cash bonuses. Hall’s totaled $500 000, according to the Times. One school, Parks Middle School, “improved” so much that it forfeited $750 000 in state and federal aid.

To gather evidence of a conspiracy that might convince a jury, Georgia state investigator, Richard Hyde, persuaded one of the teachers who was allegedly part of the scheme to wear a secret recording device. But evidence of a different kind had come to light five years earlier. In December 2008, the Atlanta Journal-Constitution drew attention to what seemed like suspiciously large and abrupt jumps in test scores. That initial investigation expanded into a five-year project in which three reporters and two database specialists gathered and analyzed test scores from 69 000 schools in 14 743 districts in 49 states.

The scores from Atlanta and few other districts stuck out as anomalous. As reported last June, some of those school districts are taking advantage of the Atlanta Journal-Constitution study to identify cheating educators.

Organized crime and electoral fraud

Similar statistical investigations can be found on the arXiv e-print server. Last month two physicists, Salvatore Catanese and Giacomo Fiumara and mathematician Emilio Ferrara, all from the University of Messina in Sicily, demonstrated that they could pick out organized criminal activity from cell phone records by looking for statistically anomalous behavior.

My favorite example—because it’s so similar to the Atlanta cheating scandal—was the study posted last year by Dmitry Kobak of the electrical and electronic engineering department of Imperial College London and two unaffiliated coauthors, Sergey Shpilkin and Maxim Pshenichnikov. Here’s the abstract:

Here we perform a statistical analysis of the official data from recent Russian parliamentary and presidential elections (held on December 4th, 2011 and March 4th, 2012, respectively). A number of anomalies are identified that persistently skew the results in favour of the pro-government party, United Russia (UR), and its leader Vladimir Putin. The main irregularities are: (i) remarkably high correlation between turnout and voting results; (ii) a large number of polling stations where the UR/Putin results are given by a round number of percent; (iii) constituencies showing improbably low or (iv) anomalously high dispersion of results across polling stations; (v) substantial difference between results at paper-based and electronic polling stations. These anomalies, albeit less prominent in the presidential elections, hardly conform to the assumptions of fair and free voting. The approaches proposed here can be readily extended to quantify fingerprints of electoral fraud in any other problematic elections.

As for Rutherford, I remain puzzled by his attitude toward statistics. The famous experiment that Hans Geiger and Ernest Marsden performed in 1909 at the University of Manchester under his direction revealed the existence of the atomic nucleus—after Geiger and Marsden had laboriously tallied the rare backward reflections of alpha particles from gold foil.

From bending flames to flying cars

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In January 1800 Thomas Young wrote to the secretary of the Royal Society, Edward Whitaker Gray, to outline his recent “experiments and inquiries respecting sound and light,” as he titled the letter.

Among the findings that Young reported was the generic deflection of fluids near a boundary. Just as a stream of air blowing over water will raise a dimple, he wrote, a candle’s flame will be drawn toward a stream of air. In both cases, and in others, proximity to a surface reduces the local pressure, leading to a net force on the stream.

The effect is not named after Young, however. That honor was bestowed by the aeronautical engineer Theodore von Kármán on his fellow engineer and near contemporary, Henri Coandă. Born in 1886 in Bucharest, Romania, Coandă started off as an artillery officer in the Romanian army. But after six years of military service, during which he was able to pursue his passion for aeronautics, he left Romania for Paris in 1909 to enroll at the École Nationale Supérieure d’Ingenieurs de Construction Aéronautique.

TwoStamps

Coandă’s first job after graduation was with Gianni Caproni’s aircraft factory in Milan, Italy. There, he designed and built an aircraft, the Coandă-1910, that made use of his namesake effect. Depicted on the two stamps above, the Coandă-1910 resembled other aircraft of the time, but with a crucial difference: Instead of spinning a propeller, its four-cylinder piston engine powered a fan that expelled air back along the fuselage. Whether the Coandă-1910 ever flew or was even capable of flight has not been established.

Coandă’s effect has had a more successful life. Its natural manifestations include the diversion of air streams over mountainous terrain and the squirting of blood from the heart’s left ventricle into the left atrium during a disorder known as mitral regurgitation. Among the effect’s practical applications are boundary-layer control systems, which blow engine exhaust over wings to boost lift at low air speeds, and HVAC diffusers, which extend the reach of cooled or heated air.

My favorite application of the Coandă effect is the Avro Canada VZ-9 Avrocar, a flying car developed in the 1950s for the US Air Force and US Army. The VZ-9 looked more like a flying saucer than a car with wings. A central, upward-facing intake drew air into a centrifugal compressor, which directed the flow into three jet engines that were arranged symmetrically around the outside of the compressor like the fireworks in a Catherine wheel. Ducts directed the exhaust down (for lift) and out (for control).

As you can tell from the video, the VZ-9 could actually fly, albeit in somewhat wobbly way. It flew at a maximum speed of 119 mph, but never lifted more than a few feet off the ground. The pitching evident in the video was never eliminated. The project was canceled in December 1961.

By contrast, the Coandă effect remains in good health. Using Google Scholar, I came across several recent papers that evoked it, including

I also found a paper posted last year to the arXiv e-print server by Teresa López-Arias of the University of Trento in Italy. Having discovered Young’s letter to Gray, she posed the question whether the Coandă effect should really be called the Young effect.

Humanities envy

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While browsing the Proceedings of the National Academy of Sciences last month, I noticed a commentary that bears the intriguing title “The science in social science.” Although the author, anthropologist Russell Bernard of the University of Florida, does indeed discuss the science behind economics, psychology, and other disciplines, the commentary’s main target was the public’s low appreciation of the benefits of social sciences. As Bernard puts it in his abstract:

A recent poll showed that most people think of science as technology and engineering—life-saving drugs, computers, space exploration, and so on. This was, in fact, the promise of the founders of modern science in the 17th century. It is less commonly understood that social and behavioral sciences have also produced technologies and engineering that dominate our everyday lives. These include polling, marketing, management, insurance, and public health programs.

At first, Bernard’s defensive tone led me to believe he had succumbed to a condition known as physics envy, the feeling of inferiority among some social scientists that their disciplines lack the mathematical and empirical rigor of physics. Lest you think that physics envy is an imagined malady, consider the opinion piece by two political scientists, Kevin Clarke and David Primo of the University of Rochester, that appeared last March in the New York Times. It’s entitled “Overcoming ‘physics envy.’”

But rather than argue, as Clarke and Primo do, that social scientists shouldn’t strive to frame their ideas as testable theories, Bernard convincingly recounts how the fruits of the social sciences pervade and enrich our daily lives.

Sicinius Velutus and Henry V

Although I doubt physicists will contract anything that might be called social sciences envy, there is evidence here and there that physicists and their professional relatives increasingly recognize the benefits of greater exposure to the arts and humanities.

Writing for the Sacramento Bee, Marisa Agha reported recently that a small and growing number of Caltech undergraduates are choosing majors like English and history and coupling them with a science or math major. At the university where I did my bachelor’s degree, Imperial College London, the undergraduate curriculum features an expanded range of optional classes in the humanities, including the delightfully titled Global History of Twentieth Century Things.

The benefits of studying humanities extend beyond the traditional goal of creating well-rounded graduates through a balanced curriculum. If you’ve cavorted about a stage in Elizabethan dress reciting Shakespeare, then giving a talk at a meeting of the American Physical Society will be as easy as setting dogs on sheep (Sicinius Velutus in Coriolanus). If you’ve argued in ten pages for—or against—the case that the Austro-Hungarian Empire’s inherent instability was the principal cause of World War I, then writing a three-page paper in Applied Physics Letters will be as easy as conquering France or speaking French (if you’re Henry V in Henry V, that is).

The civl flag of the Austro-Hungarian Empire. The empire's instability was a principal cause of World War I.

The civil flag of the Austro-Hungarian Empire. The empire’s instability was a principal cause of World War I—or not.

When scientists study humanities, society wins. Dealing with climate change, taming terrorism, and ending hunger are big, important problems whose ultimate solutions are unlikely to be wholly technical. Knowledge of human behavior and history, and the ability to understand and communicate with people, will be needed too.

Although Steve Jobs was talking about a tablet computer, the iPad2, when he made the following remarks, their sentiment is profound and apt for 21st-century scientists and engineers:

Technology alone is not enough . . . It’s technology married with the liberal arts, married with the humanities, that yields us the results that make our hearts sing.

Spacetime bubbles in the South Pacific

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When looking for things to post on Physics Today‘s Facebook page, one of the places I frequent is the arXiv eprint server, especially its section on popular physics. There, earlier this week, I noticed a paper that bears the intriguing title “Possible bubbles of spacetime curvature in the South Pacific.”

Written by Benjamin Tippett of the University of New Brunswick, Fredericton, the paper has an abstract that is even more intriguing than its title. The abstract begins,

In 1928, the late Francis Wayland Thurston published a scandalous manuscript in purport of warning the world of a global conspiracy of occultists. Among the documents he gathered to support his thesis was the personal account of a sailor by the name of Gustaf Johansen, describing an encounter with an extraordinary island. Johansen`s descriptions of his adventures upon the island are fantastic, and are often considered the most enigmatic (and therefore the highlight) of Thurston’s collection of documents.

As described by Johansen, buildings and other objects on the island were distorted, as if the geometry of the place was “all wrong.” To Tippett, who specializes in general relativity, the distortions could plausibly have arisen from the gravitational lensing effect of spacetime bubbles. In his paper he works out the properties of the bubbles. Unfortunately—his word—he concludes that

the required matter is quite unphysical, and possesses a nature which is entirely alien to all of the experiences of human science. Indeed, any civilization with mastery over such matter would be able to construct warp drives, cloaking devices, and other exotic geometries required to conveniently travel through the cosmos.

I’m far from expert enough to comment on Tippett’s mathematical analysis, but I have no reason to doubt its soundness. Tippett has published three papers in Physical Review D in the past three years: “Gravitational lensing as a mechanism for effective cloaking,” “Gravitational collapse of quantum matter,” and “Prolate horizons and the Penrose inequality.”

I can say, however, that Thurston and Johansen, whom Tippett presents in his paper as real people, are fictional. They appear as characters in H. P. Lovecraft’s 1926 short story “The Call of Cthulhu.” Cthulhu itself is a malevolent, grotesque, and powerful alien that lies dormant in an underwater city beneath the South Pacific, posing a threat to humanity if it wakes. Lovecraft’s description of the monster was so compelling that it has spawned its own fictional universe in which other writers have created, and continue to create, works—including the role playing game shown here—that extend and enrich Lovecraft’s original plot.

Tippett surely did not mean to deceive the readers of arXiv with his mix of fantasy and general relativity. Not only is Lovecraft’s story too well known, but Tippett, who belongs to a group of physics podcasters, described his paper on the group’s website on the same day that he posted it to arXiv.

I, for one, enjoyed Tippett’s playful piece. Indeed, given how many serious papers I have to read, it provided welcome relief.

Pretending to hypothesize

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For Physics Today‘s February 2003 issue, I wrote a news story about a paper in Physical Review Letters. In the paper, Dieter Braun and Albert Libchaber described how DNA molecules in solution, if confined in a small vessel and subjected to a steep temperature gradient, would form local concentrations that are 1000 times higher than in the rest of the vessel. The topic is potentially of monumental importance. High concentrations are needed for a primordial soup to beget the self-replicating molecular precursors of life—at least as we know it.

Now if you’d read the PRL paper before my PT story, you might have formed the impression that Braun and Libchaber set out to elucidate a physical mechanism that could have promoted the origin of life. Their clear, methodical description suggested, but did not state, that they were testing a hypothesis.

In fact, as I found out when I interviewed him, Braun stumbled on the effect as a byproduct of a quite different experiment to do with the nonequilibrium heating of reactants. The accidental nature of the discovery is absent from the PRL, where it might have been a distraction, but present in my story, where it added dramatic interest.

Among McNeill Alexander’s research interests is the storage and release of energy in the muscles and tendons of kangaroos and other mammals. CREDIT: Chris Samuel

Braun and Libchaber’s discovery came to mind yesterday when I encountered a paper by Darrell Rowbottom and McNeill Alexander, which appears in the latest issue of Science in Context. Rowbottom is an associate professor of philosophy at Lingnan University, a public liberal arts college in Hong Kong. Alexander is a professor emeritus of biology at Leeds University in England. Together they sought to determine how often research papers in Alexander’s field, biomechanics, are framed as tests of hypotheses.

Why would anyone embark on such an investigation you might ask. The paper’s introduction hints at an answer. Alexander recounts what comes across—at least to me—as a troubling remark about funding from a fellow biomechanicist. The unnamed colleague told Alexander that he did hypothesis-driven research because that’s what the UK’s Biotechnology and Biological Sciences Research Council favors. “No hypothesis, no money” was the implication.

Some philosophers of science and some scientists regard the testing of hypotheses as the epitome of the scientific method, especially when it entails predicting a previously unmeasured phenomenon. A prime example is Arthur Eddington’s 1919 verification of the bending of starlight by the Sun’s gravity, a prediction of Albert Einstein’s theory of general relativity.

On the other hand, physicists and other scientists value curiosity-driven research. Indeed, the list of physics Nobel laureates abounds in people who were looking for something that they thought might be interesting but who weren’t testing a carefully formulated hypothesis. The most recent laureates, Saul Perlmutter, Adam Riess, and Brian Schmidt, were surprised by their discovery of dark energy.

Presentational hypotheses

Biologists, note Rowbottom and Alexander, tend to favor hypothesis testing, whereas physicists are more tolerant of open-ended investigations or, to use the perjorative term, “fishing expeditions.” Which group would biomechanists, who apply physics to biology, most resemble?

To find out, Rowbottom and Alexander looked at 50 papers each from the Journal of Experimental Biology and the Journal of Biomechanics. All the papers were drawn from single volumes published in 2007 and 2008. They classified the papers as H (actually testing a hypothesis), E (exploratory; not testing a hypothesis), P (presenting a hypothesis but not really testing one), and S (suspected of presenting a hypothesis but not really testing one). A fifth category O (for “other”) accounted for papers that couldn’t be clearly assigned to one of the other four categories.

If the P category seems odd, consider this example. In their J Exp. Bio. paper, Maria Almbro and Cecilia Kullberg sought to test “whether the flight performance of an insect . . . is affected by variation in body mass due to feeding.” But according to Rowbottom and Alexander, the authors, by their own admission, already knew that sated and starving insects (butterflies, in fact) fly differently. Even though Almbro and Kullberg presented their research as hypothesis testing, what they were actually doing, argue Rowbottom and Alexander, was measuring a known effect.

In all, Rowbotton and Alexander found that 58% of the papers purported to test hypotheses, of which two thirds really did. The remaining third used, or were suspected of using, hypothesis testing solely as a presentational device. Not one of the 100 papers was classified as E for exploratory. Summarizing their findings, Rowbottom and Alexander write:

Overall, therefore, it is reasonable to conclude that biomechanists have a bias towards presenting their research as testing hypotheses, and (especially) prefer not to present their research as if it bears no relation to hypothesis testing. Needless to say, this could be mainly pragmatic, rather than reflect widespread agreement on what counts as good scientific practice (or genuine scientific activity). If biomechanists suspect that their chances of publication (and/or funding) will be increased by presenting their work in a particular way, then many will do so even if doing so is inaccurate.

I find Rowbottom and Alexander’s findings somewhat shocking. Although I can’t be sure, I think that Braun and Libchaber omitted the serendipitous nature of their research for the sake of clarity. Their presentation certainly helped me understand what they’d measured. However presented, their results stand by themselves.

But it would damage science if a bias against exploratory research in biomechanics and in the rest of biology stifled not only the presentation of research but also its practice. Before Rowbottom and Alexander started their investigation, Alexander asked 11 “well-regarded biomechanists with a range of experience” to categorize what they considered to be their best three papers. Fifteen percent were fishing expeditions.

Edward Condon’s reflections on the first 60 years of quantum physics

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On 2 December 1960 Edward Condon stood in the auditorium of the Natural History Museum in Washington, DC, to address the 1500th meeting of the Philosophical Society of Washington. The topic of his talk was another scientific milestone. Sixty years before, at the 19 October meeting of the German Physical Society in Berlin, Max Planck presented his radiation formula for the first time; quantum mechanics made its public debut.

Edward Condon

Condon (shown here) was well qualified to survey the history and progress of quantum physics. After earning his PhD in physics in 1926 at the University of California, Berkeley, he moved to Goettingen to work with Max Born. That same year he published what is perhaps his most famous contribution to physics: His quantum mechanical extension of James Franck’s semiclassical description of vibronic transitions in molecules. In 1929 he and Philip Morse wrote Quantum Mechanics, the first English-language textbook on the topic.

Besides witnessing and participating in the establishment of quantum mechanics, Condon had another early experience that I think prepared him for delving into the subject’s history. Between leaving high school and attending university, he spent three years as a reporter for the Oakland Inquirer and other newspapers.

A reporter’s curiosity and tenacity are evident in Condon’s Washington talk, which appeared in written form in the October 1962 issue of Physics Today. Fascinated by how Lord Rayleigh and other great old physicists of the time struggled to accommodate Planck’s formula within their classical worldviews, he dug into their papers and memoirs and quoted them extensively. Even Planck himself had difficulty, as evidenced from the excerpt that Condon quoted from Planck’s autobiography:

My futile attempts to fit the elementary quantum of action somehow into the classical theory continued for a number of years [actually until 1915] and they cost me a great deal of effort. Many of my colleagues saw in this something bordering on a tragedy. But I feel differently about it, for the thorough enlightenment I thus received was all the more valuable. I now knew for a fact that the elementary quantum of action played a far more significant part in physics than I had originally been inclined to suspect, and this recognition made me see clearly the need for the introduction of totally new methods of analysis and reasoning in the treatment of atomic problems.

In all, Condon devoted five of nine pages of his Physics Today article to his inquiries into the acceptance of quantum mechanics among physicists. That editorial choice, plus his emphasis on his own fields of study, atomic and nuclear physics, left him little room to cover the application of quantum mechanics to condensed matter and field theory. Still, I urge you to read the fascinating article.

And if you want to learn more about Condon, I recommend another Physics Today article. In “Edward Condon and the cold war politics of loyalty,” which appeared in December 2001, historian Jessica Wang discussed the groundless political persecution that Condon faced during his distinguished and productive career.

The creativity factor

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Last year two developmental psychologists from Cornell University, Stephen Ceci and Wendy Williams, published a paper in the Proceedings of the National Academy of Sciences entitled “Understanding current causes of women’s underrepresentation in science.” The paper caused a stir. Ceci and Williams attributed the low proportion of women in physics and other hard sciences to the choices made by girls and women.

My modest response to the paper was to question whether the choice to avoid the hard sciences is truly free. In their recently posted preprint, Theodore Hill and Erika Rogers looked more deeply into the question of choice. Referring to Ceci and Williams’s work, they wrote:

Even if the “women’s preference” conclusion is accepted, the original question of “Why?” remains unanswered, and, perhaps more importantly, so does the question of what could or even should be done about it. Do the majority of women prefer not to go into the hard sciences because of their own limitations in either aptitude or attitude (i.e., they simply don’t have the talent, or they think they don’t have the talent), or because there’s something intrinsically unappealing to them about these fields? And what about the women who do go into these fields, and then leave? The issue of raising children simply does not account for the smaller influxes and larger exoduses observed in hard science careers over others. Is there some other important common factor that should be considered?

Unlike Ceci and Williams, Hill and Rogers are hard scientists. Hill is professor emeritus of mathematics at the Georgia Institute of Technology. Rogers is retired from California Polytechnic State University, where she was a professor of computer science. Perhaps because of their backgrounds, Hill and Rogers seized on a what they perceived to be a glaring limitation of previous studies of gender gaps:

The self-described “top researchers” in the gender gap in science seem to have completely ignored an important and compelling factor. In spite of acknowledging up front “the kind of intense, highly creative thinking required of mathematicians,” they have omitted the well-studied issue of gender differences in creativity. In ignoring the creativity factor, the science gender gap experts have greatly underestimated the potential importance of a completely different set of both biological and societal factors which may “conspire to limit talented women and girls”. Consequently, decision makers are thereby missing significant opportunities for constructive improvements.

Hill and Rogers note that experts in the field of gender differences in creativity often distinguish two facets of creativity: creative ability and creative productivity. Studies of the former facet are inconclusive: There is no strong evidence that men have more creativity ability than women. But Hill and Rogers found a broad consensus about creative productivity: With the exception of creative writing and acting, men outproduce women in architecture, music, science, and other creative fields.

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Given that a successful mathematician or physicist must be both creative and productive, Hill and Rogers wondered if creativity could be a significant factor in explaining the dearth of women in the hard sciences. To answer that question, they reviewed studies of creative productivity with an eye out for possible gender differences. They found three possible factors:

  • Playfulness. Men more than women are willing to engage in playful, seemingly irrelevant activities that sometimes lead to innovative ideas. Hill and Rogers cited card- and Go-playing mathematicians at Bell Labs. I wrote two years ago about Andre Geim and Konstantin Novoselov’s practice of routinely devoting 10% of their time to “crazy things that probably won’t pan out at all, but if they do, it would be really surprising.” Geim and Novoselov’s playfulness helped them win a Nobel Prize.
  • Curiosity. Studies have shown that on average men are significantly more curious than women. “Curiosity,” according to one psychologist quoted by Hill and Rogers, “functions as an adaptive motivational process related to the pursuit of novelty or challenge” and could, Hill and Rogers speculate, help explain gender difference in creativity.
  • Risk taking. Hill and Rogers didn’t cite any studies to support the claim that men take more risks and endure failure more readily than women. But it’s a widely held view. To prove his and Robin Warren’s ridiculed theory that Helicobacter pylori causes stomach ulcers, Barry Marshall drank a petri dish of the bacterium, which first gave him nausea and then, within eight days, gastritis. Antibiotics cured him.

Hill and Rogers take seriously—as any scientist should—the possibility that men could be innately more creative than women. But they also note that there are significant cultural and societal reasons for the gender gap in creativity. Society, unlike our genetic programming, can be changed.

Indeed, the most valuable contribution of Hill and Rogers’s work, it seems to me, is to get us thinking about how to create environments where girls and women can develop their creativity and can indulge, as Hill and Rogers put it, in “‘unladylike’ playful behavior from getting dirty to tearing devices apart.”

As an exemplar of that approach, they cite Stanford University’s Hasso Plattner Institute of Design, known popularly as the d.school. According to the school’s website, “Students and faculty in engineering, medicine, business, law, the humanities, sciences, and education find their way here to take on the world’s messy problems together.” Besides nurturing creativity, Stanford’s d.school also trains students to deal with failure.

Hill and Rogers conclude by urging that more resources be devoted to studying and nurturing creativity.

In the meantime, we feel that changes enhancing and encouraging a “culture of creative opportunity” for students and faculty could be implemented effectively and quickly within current academic environments, particularly those with a view to improving women’s representation in the hard sciences.

If Hill and Rogers are right and if we follow their advice, followup studies by Ceci and Williams will register a welcome rise in the number of girls and women choosing to pursue physics.