H1 Consider the motions of the bodies both in the original frame of reference and in another frame that moves with velocity v0 relative to the first one. Apply the Galilean transformation formulae.

H2 Be careful, the transformation principle due to Galileo Galilei applies only to inertial reference frames. The idea that Ann simply observes Bob moving towards her with a speed of 1 m s−1 is false.

H3 It is easier to solve the problem in a frame of reference fixed to the cart. A vector diagram of velocities, superimposed on a geometrical one showing the initial situation, should prove helpful.

H4 It is helpful to describe Joe's motion using a reference frame moving with the river water; imagine that we are in a boat that drifts with the river. Using this frame of reference, a suitable optical analogy and the application of Fermat's principle can help us to find Joe's optimal trajectory.

H5 The description of the disc's motion in a frame of reference fixed to the table is not easy. Try using a reference frame moving with the conveyor belt.

H6 The task can be tackled in several ways. One possibility is to analyse the turning process in an appropriate projection of phase space, namely in the vx– vy coordinate system. Another good idea is to use an inertial frame of reference moving relative to the ice in a suitably chosen direction.

H7 From the tangential and centripetal components of the acceleration, determine the horizontal and vertical ones.

H8 Finding accurate time intervals for the two sections of the motion is very difficult. To answer the question as posed, it is easier to compare an underestimate of the time to cover arc AP with an overestimated time for arc PB.

H9 Show that the axis of symmetry of a parabola makes an angle with the tangent to the parabola at any point P that is half the angle it makes with the line connecting P to the focus.

H10 Instead of using calculus, let us try to solve the problem using a variety of techniques, e.g. by investigating the number of real roots of a quadratic equation, or by using the properties and geometric representations of relevant vectors.

A little while ago I was asked to give a lecture at the very elegant Weisman Art Museum in Minneapolis on an assigned title: “Elegance in Physics.” As I get older, the things I'm asked to do get stranger, so I wasn't surprised. Alarmingly, the older I get, the stronger is my inclination to do the peculiar ones. So I accepted the invitation, and soon found myself brooding, not, as I had imagined, about the glory of the eternal verities, but about the highly contentious nature of elegance in physics.

Here is the first such difference of opinion I came upon. In a lecture at Fermilab with a title similar to the one I was given, Subrahmanyan Chandrasekhar talked about “harmoniously organizing a domain of science with order, pattern, and coherence.” He cited five examples of such pinnacles of exposition, one of them being Paul Dirac's celebrated book, Principles of Quantum Mechanics. “The translucence of the eternal splendor through material phenomena,” Chandrasekhar remarked, “[is] made iridescent in these books.”

Keeping that iridescent translucence firmly in mind, consider the following remarks of the eminent mathematician Jean Dieudonné:

What is Dieudonné talking about? He is addressing the approach to quantum mechanics laid out in Dirac's book.

Elegance in physics is as much in the eye of the beholder as it is in any other field of human endeavor. Dirac's formulation appeals to physicists because, by being a little vague and ambiguous about its precise mathematical structure, it enables them to grasp and manipulate the physical content of the theory with a clarity and power that would be greatly diminished if one were distracted by certain complicating but fundamentally uninteresting mathematical technicalities. But for mathematicians, those minor technical matters lie at the heart of the subject. Quantum mechanics becomes ill-formulated and grotesque if it does not properly rest on impeccable mathematical foundations.

Friday, December 6th. Arrive Stockholm 8 am, luggage stuffed with white tie costume, dark suits, evening gowns, newly acquired white shirts and ties. Light rain. Grand Hotel selectively grand. Bathroom magnificent but closets insufficient for two Nobel guests. No bureaus whatever. After dinner find hosts and Cornell physics colleagues Dave Lee and Bob Richardson newly arrived from Göteborg, wearing tiny gold lapel pins so reporters, autograph collectors can tell laureates from guests. Bob has bad cold. Get perfect 8 hours sleep, but first night always easy.

Saturday, December 7th. Breakfast buffet at Grand phenomenal, and attended by many old friends from glory days of superfluid helium-3. Black stretch limos—one per laureate—take physics and chemistry winners to lectures. Guests follow in tour buses. Lecture hall surprisingly small. Front rows reserved for Nobel guests. Physics lectures evocative of scientific memories from early 1970s. Bliss was it in that dawn to be alive. Chemistry talks also fun since buckyballs really physics. Or is superfluid 3He really chemistry? Both prizes for something discovered accidentally while looking for something else. Back to Grand in dark. Get report on literature prize lecture by Wislawa Szymborska from those who cut chemistry to attend. Who would have expected parallel sessions? Awake half the night.

Sunday, December 8th. Laureates busy all day; guests free, weather dry, city beautiful. Collapse at 2 pm, awakening from nap in darkness at 3. Bus to opulent reception. Reunion of old 3He crowd at delicious dinner. Laureates can't make it, having mandatory “Informal dinner (dark business suit)” at Academy of Sciences. Awake most of night.

Monday, December 9th. Guest status good for front row seats at economics lecture. Theory of auctions. Integrals and derivatives. Like physics except physics works. American laureates have lunch with ambassador. Poor laureates. Guests have learned to skip lunch between breakfast buffet and late afternoon reception. Today's event dwarfs yesterday's: Apotheosis of Informal Dress. Black suit blends right in. Succumb to earthly delights until time to depart for dinner in gorgeous baroque clubroom with Swedish Cornell alumni. Sleep all night.

Tuesday, December 10th. Big day. Women have hair set in morning and are confined to quarters until afternoon. Laureates off at a mandatory rehearsal (casual). Take long walk along water to check out City Hall. Many delivery vans, mysterious stacks of wood.

One of the questions asked of lecturers in this series is “What first drew you to your discipline?” What first drew me to physics was magic. It came in two varieties: relativity and quantum mechanics. I know that the magic of relativity had grabbed me before I was 16, because I remember my first day of high-school physics in 1951. The teacher was a tight-lipped gentleman who, it was rumored, had risen to the rank of Colonel in World War I. He liked to throw hard rubber erasers at people he thought were dozing.

“Physics,” the Colonel told us, “is about laws that govern the behavior of matter. There is, for example, the law of the Conservation of Mass.” My hand shot up. “Doesn't relativity say that mass is not conserved?” There was a long terrifying silence. “I don't know anything about relativity,” snarled the Colonel at last. “Do you?” I never again inquired about anything not in the textbook: Modern Physics, by Charles E. Dull.

So I must have known something about relativity when I was sixteen. The magic of it was this: If you could move at 99.98% of the speed of light, then in a little over four years you could go four light years, and get to the nearest star. But—here was the magic part—you would be only a month older when you got there. Same thing on the way back. When you got home everybody would be eight years older, but you would have aged only two months. If you did it three or four times you could come back younger than your own kids!

Just as amazing, if on the way out in your spacious mile-long rocket, you passed another one-miler on the homebound run and measured its length as it flashed past, you would find it to be only one foot long, and everybody in it, flattened to the thickness of sheets of paper. And, most mysterious of all, the occupants of the home-bound rocket would find that you and your rocket were correspondingly squashed. How could this be? How could each of two rockets be shorter than the other? I desperately wanted to understand.

I met Ken Wilson in 1952, when I was 17 and he was 16. We were both freshmen in the Harvard class of 1956, which produced an exceptionally large number of well-known physicists. As I remember Ken and I were in the same introductory German class, but it might have been the required freshman composition course, which met in the same building. What I remember for sure is that I got an A and Ken got a B. This was the only time in my life that I understood something better than he did.

What I remember most about Ken from 1952 is that although he was 16, he looked about 13. I don't think he looked 16 until he got tenure at Cornell. An important part of his youthful look was that when somebody said something that really pleased him, his face would light up with such a sweet smile that it warmed your heart, like the first smiles of a baby.

Indeed, there was a performance at the 1964 Cornell Physics Department Christmas party, the year I got here, in which graduate students sang satirical songs about their Professors. What they sang about Ken was based on a song from South Pacific (“Bloody Mary is the one I love, now ain't that too damn bad!”) It went “Kenny Wilson is the cutest Prof, but mesons ain't much fun.” Mesons may indeed not have been much fun, but within ten years Ken was to provide theoretical physicists with the best opportunities for fun that they had since the invention of quantum mechanics.

Ken and I were math majors at Harvard. He had a formidable reputation as a mathematician and was at least two years ahead of me in the math curriculum. It being Harvard, however, by general agreement, which I believe Ken subscribed to, he was only the second-best mathematician in our class. I found this abundance of superior talent discouraging. To escape from mathematicians who were too smart to compete with, I stayed at Harvard for graduate school, but switched to physics. Out of the frying pan into the fire.

In 1959 Ken reappeared in Cambridge as a Junior Fellow. Much to my surprise, he too had become a physicist, irritatingly fast, at CalTech.

Professor Mozart burst into my office, waving the January 1992 issue of Physics Today. “What are you doing here, W. A.?” I greeted him in surprise. “I thought you were abroad fund-raising for the SSC!”

“Just got back,” he gasped, having apparently run up all five flights of stairs. “Castro says he'll provide all the cigars if we can persuade Bush to lift the sugar quota. Just sent Bromley a memo. Don't see how Congress can drag its feet any longer—especially when we remind them that accelerator physics gave us ride-on lawn mowers, sliced bread, and the compact disc. But what about this response to your call last May for the abolition of journals in favor of electronic bulletin boards? Ten letters to the editor—all but two hostile? As a pundit, you've got it made!”

“Thank you,” I replied sourly, “but the fact is I received even more letters that were wildly enthusiastic—by far the biggest response I've ever had.”

“Don't tell me,” he said, lighting up an enormous Havana. “All the favorable correspondence came by email. No copies to Physics Today. Shun the print media. Matter of principle.”

“You've got it,” I confirmed, suppressing a gasp myself. “My supporters are all children of the network. I doubt they even use the telephone anymore, except as ancillary to a modem. They want me to lead the way into the shining electronic future, writing software, designing hardware, lobbying professional societies, organizing boycotts, raising funds …”

“Leave the fund-raising to me,” he ordered through the smoke. “Your immediate problem is to answer your critics. How could you have expected to attack the refereeing process and come out unscathed? Don't you realize most people can't write an acceptable laundry list without peer review? Without referees we'd soon be promulgating inchoate blather. Can you imagine what Hamlet must have looked like the first time Shakespeare submitted it? Why, somebody once told me that Othello is what Titus Andronicus turned into after half a dozen exchanges. And you want to abolish refereeing!”

“Never mind how peer review operates under the current system,” I interrupted. “What none of the critics have noticed is how much better it will work in Computopia.”

“No doubt you're thinking,” he murmured through the fog, eyes half closed, “of a parallel bulletin board of criticisms and errata.”

Once upon a time everybody knew why measurements in quantum mechanics don't reveal pre-existing properties. It was because the act of acquiring knowledge unavoidably messes up the object being studied. What you learn is not intrinsic to the object, but a joint manifestation of the object and how you probe it to get your knowledge.

In 1935 this state of happy innocence was forever dispelled by Einstein, who with Boris Podolsky and Nathan Rosen discovered how to learn about an object by messing up only some stuff it left behind in a faraway place. They concluded that knowledge acquired in this way was indeed about pre-existing properties of the object, revealed—not created—by the act of probing the stuff left behind. Bohr, however, insisted their conclusion was unjustified, and 30 years later John Bell proved that no assignment of such pre-existing properties could agree with the quantitative predictions of quantum mechanics.

A couple of years ago Lucien Hardy [1] gave this tale an unexpected twist, by finding a charming variation of the Bell–EPR argument. Hardy's theorem is even simpler than the argument of Daniel Greenberger, Michael Home, and Anton Zeilinger that I enthused about in this column four years ago. The reason he was able to pull the trick off, and the reason, I suspect, nobody had noticed so neat an argument for so long, is that Hardy's analysis applies to data that are not correlated strongly enough to support the argument of EPR. But they do give rise to an argument every bit as seductive, which Hardy is then able to demolish with surprising ease. Parts of the formulation I give here of Hardy's gedankenexperiment are similar to those of Henry Stapp [2] and Sheldon Goldstein [3].

We consider two particles that originate from a common source and fly apart to stations at the left and right ends of a long laboratory. At the left station we can experimentally determine the answer to one of two yes–no questions, A or B. There is a choice of two other yes–no questions, M or N, to be answered by experiment on the right. Hardy provides questions A, B, M, and N, and a two-particle state |Ψ〉 for which the answers to the questions have the following features: […]

During the recent presidential election, I dreamt that two of the candidates had concluded from interviews with focus groups that there might be some anxiety among the American public over the foundations of quantum mechanics. Concerned that by homing in on so esoteric a topic they could lose the attention of the people, the two men had made a direct assessment of public interest by quietly employing their rhetorical skills in unpublicized lectures at local events such as church barbecues, farmers’ markets, or demolition derbies. I could never learn soon enough about these performances, always arriving just as a lecture ended. By conducting exit interviews, however, I managed to put together fragmentary transcripts of what took place, which were so vivid that I was able to jot them down in the morning.

In a subsequent dream I read these texts back to my interviewees, who agreed that although I had failed to capture the full brilliance of the argumentation, I had at least succeeded in conveying the flavor of the insight these remarkable men brought to the problems that have puzzled and delighted physicists for so many years.

The candidates’ experiments were not a success. Both men concluded that the time was not ripe to bring these great issues before the public. Indeed, in my third and final dream I was forced to endure an interminable postelection analysis on public TV, in which the panelists concluded that by distracting the two candidates from more pressing issues, their love of quantum mechanics had contributed significantly to their defeat. I'm sure there are lessons for physicists from this cautionary tale, but I offer here only the texts of the lectures themselves, which I believe form an important chapter in the intellectual history of our times.

The first lecture

Now it's really very simple, OK? Over here's an electron, moving toward this wall, kind of like a cur dog slinking toward his kennel. Only there are two doors to the kennel, like the two doors in the wall here in Figure 1.

Now, over here on the other side of the wall's a screen. Now then, the point is, the electron ends up making a mark on the screen, kind of like a fly makes a speck on a kitchen window?

It seems to me evident that the system of prizes, honors, and awards in physics has run completely amok, absorbing far too much of the time and energy of the community in proportion to the benefits conferred. Yet nobody complains. Every month Physics Today routinely announces the latest crop of winners, all the major American Physical Society meetings have sessions to bestow prizes, the APS directory continues to distinguish the asterisked from the unasterisked, and nobody ever complains. Why?

To ask the question is to answer it. Indeed, merely by publishing the above paragraph I have probably already irreparably blemished my reputation in the profession, and if Physics Today has actually printed this column I imagine it can only have been after heated and prolonged editorial debate. Much of this essay, in fact, sat aging in my computer in a directory with highly restricted access for almost two years. It was finally sprung loose by the 1988 presidential campaign, which filled me with so intense a loathing for those who hesitate to speak provocative truths that I can longer restrain myself. Here I go.

Why does nobody ever complain? Nobody complains because there are two categories of physicists: those who have won prizes and those who have not. Winners cannot criticize the system. It would be rude to the donors of their prizes. It would be offensive to the committee that selected them and the people who wrote letters on their behalf. It would be a vulgar display of bad taste. It would be unseemly to criticize a system one has benefited from before others have had their chance to win.

But neither can nonwinners criticize the system. It is not that a public attack on, for example, the absurdity of election to the National Academy of Sciences might jeopardize one's own chances for immortality, for this would be a noble sacrifice. What freezes dissent for the nonwinner is that it would be perceived as sour grapes—an unbecoming outburst of petty jealousy. The only respectable stance for the nonwinner is warmly to congratulate each new crop of winners, a kind and gentle response to be sure, but one that implicitly endorses the system itself, preposterous as it is.

A few months ago I found myself living one of my milder visions of hell, trapped on a flight to Los Angeles, having forgotten to bring along anything to read but Physical Review Letters. Finishing the two articles that had inspired me to stuff it in my briefcase before we even reached the Mississippi I decided to make the best of a bad thing by taking the opportunity to expand my horizons. Scanning the table of contents, I was arrested by a title containing the word “Lagrangean.”

Funny, I thought, it's not often you see misprints so blatantly displayed. But when I turned to the article, there it was again, “Lagrangean,” in the title and scattered through the text. Well, I thought, an uncharacteristic failure of the copyediting process. The authors were foreign and apparently didn't know how to spell. Copy editors aren't physicists, the word is surely in few if any dictionaries, and so it slipped through.

But I had nagging doubts. Easily resolved, I thought: You can't write an article in theoretical particle physics without a Lagrangian, so I can check it right now. Well, it turns out to be not quite that easy. To be sure, you can't do particle physics without a Lagrangian, but you don't have to call it anything more than L, and many don't. Nevertheless, I found a Lagrangian, fully denominated, in one more article, and there it was, shimmering derisively before my eyes again: “Lagrangean.”

Now I am not a man of great self-confidence, and my secretary will testify that I am a rotten speller. Was I fooling myself? Could “Lagrangean” be right, and my conviction that it should be “Lagrangian” an orthographic hallucination induced by the absence of better things to read, like a mirage in the desert? Please ask yourself this, dear reader, before reading on: Would it have startled you?

When the plane landed in Los Angeles, I tooled up the freeway to the house of my hosts and breathlessly asked, “How do you spell ‘Lagrangian’?”

“I dunno,” said he, but she said without hesitation, “L-A-G-R-A-N-G-I-A-N,” and I felt hope for my sanity, A quick tour revealed that every book in the house on mechanics and field theory spelled it with an i. I was sane! But what was going on at Physical Review Letters?

My colleague Professor Mozart burst into my office, just back from a pro-SSC rally in Washington and still full of excitement. “The police estimated the crowd at seventy thousand, but it was at least a quarter of a million. It makes you proud to be a physicist. And to top it all off. while I was dodging tear-gas canisters, it came to me!”

“Tear gas, at a pro-SSC demonstration?” I gasped in disbelief.

“Yes,” he confirmed. “An enormous crowd, unaware that they should have been addressing their concerns to Congress, started to march toward the White House chanting, ‘Hey, hey, Allan Bromley, give us the Higgs or we won't go calmly!’ and the Secret Service must have panicked. Those teenagers can be frightening, you know. They really get quite out of control when they think we might pass up an opportunity to find the Higgs. And those MIVeBs can be pretty alarming too, when they're on the move,”

“MIVeBs?” I inquired.

“Mothers for Intermediate Vector Bosons,” he explained impatiently, unable to disguise his disdain at how out of touch I was with the Movement. “But then as the first canisters started to pop, I realized how simple the solution really was.”

“Solution to what?”

“The funding problem for the individual investigator, of course! I can't imagine why nobody has thought of it before. We simply abolish all such grants, freeing the investigators to return to the full-time pursuit of their individual science.” He settled into my only comfortable chair, beaming with satisfaction.

I've heard some zany things from Mozart before, but this one was just a little too self-serving to let pass. “Very fine for you, W. A.,” I said with ill-concealed scorn, “who loathe writing proposals and progress reports and feel no responsibility for training the next generation of physicists. But what about the more conscientious members of our profession? How are they to keep the enterprise of small science alive?”

I hadn't intended to be so brusque with him, but it really is disgusting to see how much happier he's become since his grant was cut. Undeterred by my swipe, he continued.

“You don't understand. I'm not proposing to abolish support for small science—just to stop distributing it so irrationally. Take that next generation. Why do the agencies give out so few graduate student fellowships, and only for the first few years?

On 15 August 2000, The New York Times, celebrating the new century, published a list of 10 questions that they characterized as ones physicists would like to ask their colleagues in the year 2100 if they awoke from a hundred-year sleep.

1. Are there reasons why the fundamental dimensionless parameters have the values they do?

2. What role did quantum gravity play in the Big Bang?

3. What is the lifetime of the proton?

4. Is supersymmetry a broken symmetry of nature?

5. Why is spacetime apparently four-dimensional?

6. What is the value of the cosmological constant, and is it really constant?

7. Does M-theory describe nature?

8. What happens to information that falls into a black hole?

9. Why is gravity so weak?

10. Can we quantitatively understand quark and gluon confinement?

You will not be surprised to learn that the questions were assembled at a party celebrating the conclusion of a conference on superstring theory. The Times, however, characterized them as “Physics questions to ponder,” leaving me to ponder why they were so different in character from what I would be most eager to learn from my professional descendants at the end of a hundred-year nap.

The Times inspired me to put together my own list of the questions I'd put to a colleague in 2100. The criteria for inclusion on my list are (a) that I would love to know the answer, (b) that the questions should be likely to make sense to scientists in 2100 and not just to historians of science, and (c) that the questions should have a reasonable chance of not eliciting titters at my early 21st-century naivety. Probably you'll find my list just as parochial as I found the string theorists’ list. But here it is:

The problem with giving a lecture on elegance in physics is that much better physicists have already said a lot about it. This is well-worn ground. The great astrophysicist Subrahmanyan Chandrasekhar began a lecture on “Beauty and the Quest for Beauty in Science” [1] by remarking that “The topic to which I have been asked to address myself is a difficult one, if one is to avoid the trivial and the banal.” So I cannot even comment on the risk of triviality and banality without engaging in them.

Clearly I cannot tell you about how Maxwell's equations for the electromagnetic field used to fill an entire page and require ten different letters of the alphabet for their expression, even in empty space. But then with the invention of vectors, Maxwell's equations shrank to four lines and three letters. The added insights of relativity reduced them to one letter and one line, thereby condensing the hard-won insights of Coulomb, Oersted, Faraday, and Maxwell himself to a degree of concise precision none of them could have imagined.

Nor can I wax lyrical about the extraordinary power and economy of Dirac's formulation of quantum mechanics, which makes transparently lucid the equivalence of Schrödinger's and Heisenberg's superficially different formulations of the fundamental theory, as well as simplifying many formerly complicated calculations into a few almost self-evident lines.

And certainly I cannot say anything about the great conservation laws of energy, momentum, and angular momentum, and how they can be understood as consequences of the simple symmetries of our universe—that things happen the same way regardless of when they happen, where they happen, or how they are oriented.

All of this has been said too often to repeat any of it.

What I can do is tell you about a few less lofty things: attitudes of physicists toward elegance in their discipline, and a few very down-to-earth examples of what I would consider elegant.

Physicists are ambivalent about elegance. When I received the invitation to give this lecture all I could think of was “Elegance is for tailors.” That succinct dismissal of the theme of this series is probably the most celebrated remark any physicist has ever made about the role of elegance in physics. But instead of thinking about my assigned topic, I began by worrying about who had said it.

Sometime in the mid-1980s Gloria Lubkin, the editor of Physics Today, invited me to contribute to a new column of opinion called Reference Frame. Earlier that decade I had published two articles in Physics Today. The first described my successful effort to make the ridiculous word “boojum” an internationally accepted scientific term. The second gave a very elementary way of thinking about Bell's Theorem and its implications for our understanding of quantum mechanics. These apparently suggested to Gloria that I'd make a good columnist.

I wasn't so sure. Having to produce something clever and entertaining at regular intervals was not my style. On the occasions when I'd managed to do it, it seemed like a small miracle, unlikely ever to happen again. So while I didn't say no, I kept stalling. A couple of years went by.

Then one day I discovered that Physical Review Letters, the world's most important physics journal, was doing something quite ridiculous that seemed to have escaped the attention of all the physicists I told about it. The absurd policy and the fact that nobody seemed to have noticed it made a good story. Another miracle. I sent the story (Chapter 1) to Gloria and became a columnist, joining a group of Reference Frame writers that included Phil Anderson, David Gross, Leo Kadanoff, Dan Kleppner, Jim Langer, and Frank Wilczek.

After that Gloria would phone every few months requesting more miracles. Somehow she managed to induce them. I came to regard her as my Muse. For 21 years she extracted essays I didn't know were in me. She criticized first drafts and negotiated final versions. As some of these essays reveal, my relations with editors have often been tense, but working with Gloria was always a pleasure. She knew exactly how to do her job, and she knew how to get me to do mine.

In 2009 Gloria Lubkin retired from Physics Today and the Reference Frame columns came to an end. I found to my surprise that I had produced thirty of them—one every eight issues. Not all were miracles, but surprisingly many were. As I traveled around the world of physics after 1988, giving talks at universities and conferences, I discovered that I was becoming better known for my columns than for my technical scientific papers or textbooks.

Friday, December 6. We arrive in Stockholm at 8 am. I change a heap of dollars to kronor. Light rain falls. The expected limo does not appear. Our luggage is stuffed with white-tie costume, dark suits, evening gowns, newly acquired white shirts and ties, and provisions for winter weather of all possible kinds. A minivan takes six of us and a prodigious number of bags to the Grand Hotel. We hand over a heap of kronor to the driver. Our room is not ready. I explore the public facilities. Today's Herald Tribune is posted in the men's room. Madeleine Albright is the new Secretary of State. Now the room is ready. Conserving my remaining kronor I hand the bellhop a $5 bill.

The Grand Hotel is selectively grand. The bathroom is magnificent but there are not enough closets for two Nobel guests, no bureaus whatever, and the desk drawers are stuffed with phone books. We set up camp for the week making ingenious use of all available surfaces. We go for a walk. We forgot to bring an umbrella, but never mind. The Grand Hotel provides. We cross a bridge into Gamla Stan, the old town. Cobblestones glisten. The buildings are lovely in the pale light. We return to the Grand for a brief nap. I discover I left important pills home. The Grand Hotel rises to the occasion. I am instantly connected with a soothing doctor who asks appropriate questions, consults appropriate texts, and sends me to the nearby Lion pharmacy. Pills are sold in units of 100. I have to acquire 5 times the needed number. An enormous fee for the soothing doctor is added in. I put it on the Visa card.

Night comes at 3 pm. We dine at an unpretentious little spot where I hand over my remaining kronor. We take an after-dinner walk to an ATM machine and get another heap. Back at the Grand we find Dave Lee and Bob Richardson newly arrived from Gothenburg. They wear tiny gold lapel pins throughout the week so reporters and autograph collectors can tell them from their guests. They have already been celebrating for several days in Gothenburg. Bob has a bad cold. Both are very happy and a little high. I get a perfect 8 hours sleep, but the first night is always easy.

Now that the standard model has been with us long enough to have become part of the commonplace wisdom of schoolchildren, it is high time to face head on the contentious issue of how properly to pronounce the word quark. Although only a condensed-matter theorist, I am proud to contribute what follows as a low-cost contribution to straightening out one of the annoying loose ends, others of which may have to wait considerably longer for their resolution.

As a rule, only native speakers of English hold passionate opinions on how quark is to be pronounced, and that is as it should be. One of the glories of the English tongue is that its comprehensibility is undiminished and its beauty even enhanced by the systematic mispronunciation of vowel sounds by non-native speakers. But it is a sad and ugly business when the wrong sounds emerge sporadically from the mouths of natives. Quite aside from such aesthetic considerations, it is surely the duty of us native speakers of English to set appropriate standards that the others, if they so desire, may strive to attain. Nowhere is there more need for clarification than in the hotly disputed case of quark.

The opinion of the majority is clear: Quark is pronounced to rhyme with pork. There is, however, a vocal and embittered minority, biting in its rejection of the prevailing view, whose members insist on pronouncing the word to rhyme with park. It is often argued in defense of this practice that the word is taken from the German name for a horrible yogurt-like fluid, the proper pronunciation of which unquestionably comes closer to rhyming with the English park than it does with pork. This minority argument, however, is entirely spurious. If one were to adopt the German pronunciation consistently one could indeed rhyme quark with park, but only at the price of having to say kvark, which no native speaker of English has ever been known to advocate.

Clearly the decision must be made from a study of English usage and, I would maintain, either on the basis of the Irish variety of English, out of respect for the man who imported the word from German, or on the basis of the American variety, in deference to the man who transported it into physics.