Donald L. Unger, Does knuckle cracking lead to arthritis of the fingers?
Arthritis & Rheumatism magazine, May 1998

In 1998, California physician Donald L. Unger wrote to the editors of Arthritis & Rheumatism to report a “50-year controlled study by one participant.” His mother had told him that cracking his knuckles would lead to arthritis, so for 50 years the science-minded Unger had cracked the knuckles of his left hand at least twice a day, more than 36,500 times in all, and left the right uncracked as a control. After 50 years he found no arthritis in either hand and no differences between the two hands.

“This result calls into question whether other parental beliefs, e.g., the importance of eating spinach, are also flawed,” Unger wrote. “Further investigation is likely warranted.”

The editors invited a response from Robert L. Swezey, who had published an earlier investigation in the Western Journal of Medicine. Swezey said that his own study had been inspired when his 12-year-old son’s grandmother had warned him that cracking his knuckles would cause arthritis. “It is now 22 years later and he continues to enjoy frequent KC without manifestations or evidence of arthritis.”

With motherly advice thrown into doubt, Swezey wondered whether knuckle cracking might even prevent osteoarthritis. “The possible utilization of KC by managed care providers as an economic, noninvasive, home preventative treatment for arthritis of the hands should be given further consideration,” he concluded. “A clear distinction between hand wringing related to managed care procedures and therapeutic KC will have to be made.”

(Source: futilitycloset.com)

An anecdote from Metafilter user range, answering a question about the strong nuclear force and gravity and black holes and apparently freakish coincidences in quantum physics

One of the perks of studying undergrad physics at MIT was taking third-semester quantum mechanics from someone who had an honest-to-god Nobel Prize. He (who shall remain nameless) was doing a test prep session with the class one night and at one point got to an expression that looked like this:

… at which point he stares hard at the board, then looks at us (~50 senior physics majors). Then at the board. Then us. Then back to the board, where he (a little sheepishly) reduces it to:

When we all got done laughing he retaliated with:

“Look. Experimentally, we don’t know the value of this number [points at alpha] better than within 2 orders of magnitude, and nobody can think of a way to measure it any better. The difference between pi and 3 is 5%. The simpler expression is going to hold true enough for some time between 50 years and forever. So shut up.”

Barry Mazur, Visions, Dreams, and Mathematics
August 1, 2008

If someone asks us What is X? where X is some mathematical concept, we boldly answer, for we have been well trained in the art of definitions. All the fine articulations of logical structure are at our fingertips. If, however, someone asks us What does X mean? we respond as any human must respond when explaining the meaning of something: we are thrust into the whirlwind of interpretations, intentions, aims, expectations, desires, and shades of significance that, in effect, depend largely upon the story we have woven around the concept. Consider, for example, the innocuous question:

What does it mean to find X in the polynomial equation X² = 2?

We frame a narrative the minute we open our mouths to answer this question.

Continued here.

Lee Smolin, The Trouble with Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next
2006 

My first job after getting my PhD was in 1979 at the Institute for Advanced Study, in Princeton. One of my main reasons for taking it was the hope of making contact with some living legacy of Einstein, who had died twenty-four years earlier. In this I was disappointed. There was no trace of his time there, apart from a bust of him in the library. No student or follower of Einstein could be found. Only a few people who had known him, like the theoretical physicist Freeman Dyson, were still there. 

My first week there, Dyson, very much the gentleman, came by and invited me to lunch. After inquiring about my work, he asked if there was anything he could do to make me more at home in Princeton. I had but one request. “Could you tell me what Einstein was really like?” I asked. Dyson replied, “I’m very sorry, but that’s one thing I can’t help you with.” Surprised, I insisted, “But you came here in 1947 and you were a colleague of his until he died in 1955.”

Dyson explained that he too had come to the institute hoping to get to know Einstein. So he went to Einstein’s secretary, Helen Dukas, to make an appointment. The day before the appointment, he began to worry about not having anything specific to discuss with the great man, so he got from Ms. Dukas copies of Einstein’s recent scientific papers. They were all about Einstein’s efforts to construct a unified-field theory. Reading them that evening, Dyson decided they were junk. The next morning, he realized that although he couldn’t face Einstein and tell him his work was junk, he couldn’t not tell him either. So he skipped the appointment and, he told me, spent the ensuing eight years before Einstein’s death avoiding him. I could only say the obvious:

“Don’t you think Einstein could have defended himself and explained his motivation to you?”

Certainly, Dyson replied, but I was much older before that thought occurred to me.

p. 49-50

Paul K. Feyerabend, Quantum Theory and Our View of the World inside Physics and Our View of the World, edited by Jan Hilgevoord 

When I was a student in Vienna, in the late 1940s, we had three physicists who were known to a wider public: Karl Przibram, Felix Ehrenhaft and Hans Thirring. Przibram was an experimentalist, a pupil of J. J. Thomson whom he often mentioned with reverence. Philosophers of science know him as the editor of a correspondence on wave mechanics between Schrodinger, Lorentz, Planck and Einstein. He was the brother of Hans Przibram, the biologist, and, I believe, the uncle of the neurophysiologist Karl Przibram. He talked with a subdued voice and wrote tiny equations on the blackboard. Occasionally his lectures were interrupted by shouting, laughing and trampling from below; that was Ehrenhaft’s audience.

Ehrenhaft had been professor of theoretical and experimental physics in Vienna. He left when the Nazis came; he returned in 1947. By that time many physicists regarded him as a charlatan. He had produced and kept producing evidence for subelectrons, magnetic monopoles of mesoscopic size and magnetolysis, and he held that the inertial path was a spiral, not a geodesic. His attitude towards theory was identical with that of Lenard and Stark whom he often mentioned with approval. He challenged us to criticize him and laughed when he realized how strongly we believed in the excellence of say, Maxwell’s equations without having calculated and tested specific effects.

During a summer school in Alpbach he set up his experiments in a little farmhouse and invited everyone to have a look. Leon Rosenfeld was there; so was Maurice Pryce, one of the most abrasive physicists of his generation. They went in; when they reappeared they looked as if they had seen something obscene. However all they could say was ‘obviously a Dreckeffekt’. Afterwards, in Ehrenhaft’s lecture, Rosenfeld and Pryce sat in the front row. Having described his experiments Ehrenhaft went up to them and exclaimed: ‘Was können sie sagen mit allen ihren schönen Theorien? Nichts können sie sagen. Still müssen sie sein. Sitzen müssen sie bleiben.’ (What can they say with all their fine theories? They can say nothing. They must be silent. They must remain seated.) And, indeed, Rosenfeld and Pryce, so eloquent on other occasions, did not say a single word. Ehrenhaft may not have been mainstream. But he made us think — more than many mainstream scientists before and after him.

Paul K. Feyerabend, Has the Scientific View of the World a Special Status Compared With Other Views? inside Physics and Our View of the World, edited by Jan Hilgevoord 

Is it not really strange, asks Einstein, that human beings are normally deaf to the strongest argument while they are always inclined to overestimate measuring accuracies?

These and similar examples show that science contains different trends with different research philosophies. One trend requires that scientists stick closely to the facts, design experiments that clearly establish the one or the other of two conflicting alternatives and avoid far reaching speculations. One might call it the Aristotelian trend. Another trend encourages speculation and is ready to accept theories that are related to the facts in an indirect and highly complex way. Let us call this the Platonic trend. …

Using a symmetry principle Anaximander objected that fire, earth and air seemed to be as important as water which means that the basic substance had to be different from all elements, though capable of turning into them under special circumstances. Anaximander called it apeiron - the unlimited. Parmenides then pointed out that Being was still more fundamental (water is, fire is, apeiron is - they are all forms of Being). What can be said about Being? That it is and that not-Being is not. Note that the statement BEING IS (estin in the Greek of Parmenides) was the first explicit conservation principle of the West: it asserted the conservation of Being. Accepting this argument we can infer that there is no change: the only possible change is into not-Being, not-Being does not exist, hence there is no change. What about difference? The only possible difference is between Being and not-Being, not-Being does not exist, hence Being is everywhere the same. But don’t we perceive change and difference? Yes, we do, which shows that change and difference are appearances, chimeras. Reality does not change. This was the first and most radical (Western) theory of knowledge. It is not entirely ridiculous: nineteenth-century science up to and including Einstein also devalued change.

…

Ancient atomism can be seen as an attempt to shorten the distance between basic physics (BEING IS) and common sense. Leukippos and Democritos retained one part of Parmenides’ theory (atoms are tiny fragments of Parmenidean Being) and rejected another (not-Being exists and it is identical with space).

Love of Truth is one of the strongest motives for replacing what really happens by a streamlined account or, to express it in a less polite manner — love of truth is one of the strongest motives for deceiving oneself and others.

In 1854 Commander Perry, using force, opened the ports of Hakodate and Shimoda to American ships for supply and trade. This event demonstrated the military inferiority of Japan. The members of the Japanese enlightenment of the early 1870s, Fukuzawa among them, now reasoned as follows: Japan can keep its independence only if it becomes stronger. It can become stronger only with the help of science. It will use science effectively only if it does not just practice science but also believes in the underlying ideology. To many traditional Japanese this ideology - ‘the’ scientific world-view - was barbaric. But, so the followers of Fukuzawa argued, it was necessary to adopt barbaric ways, to regard them as advanced, to introduce the whole of Western civilization in order to survive.

The lesson I draw from this sequence of events is that a uniform ‘scientific view of the world’ may be useful for people doing science — it gives them motivation without tying them down. It is like a flag. Though presenting a single pattern it makes people do many different things. However, it is a disaster for outsiders (philosophers, fly-by-night mystics, prophets of a New Age, the ‘educated public’), who, being undisturbed by the complexities of research, are liable to fall for the most simple-minded and most vapid tale.

Manjit Kumar, Quantum: Einstein, Bohr, and the Great Debate about the Nature of Reality
W. W. Norton & Company, 2010 

In the 1890s some of Germany’s leading physicists were obsessively pursuing a problem that had long vexed them: what was the relationship between the temperature, the range of colours, and the intensity of light emitted by a hot iron poker? It seemed a trivial problem compared to the mystery of X-rays and radioactivity that had physicists rushing to their laboratories and reaching for their notebooks. But for a nation forged only in 1871, the quest for the solution to the hot iron poker, or what became known as ‘the blackbody problem’, was intimately bound up with the need to give the German lighting industry a competitive edge against its British and American competitors. But try as they might, Germany’s finest physicists could not solve it. In 1896 they thought they had, only to find within a few short years that new experimental data proved that they had not. It was Max Planck who solved the blackbody problem, at a cost. The price was the quantum.

…

Driven largely by the abolition of internal tariffs after unification and French war compensation, by the outbreak of the First World War Germany’s industrial output and economic power would be second only to the United States. By then it was producing over two-thirds of continental Europe’s steel, half its coal, and was generating more electricity than Britain, France and Italy combined. Even the recession and anxiety that affected Europe after the stock market crash of 1873 only slowed the pace of German development for a few years.

David Bentley Hart, Atheist Delusions: The Christian Revolution and its Fashionable Enemies
Yale University Press, 2009

In any event, Copernicus was heir to a long mathematical tradition and—if he cared to make use of it—a tradition of physical theory that had opened the way to new models of the cosmos. And Copernicus’s contribution, to be honest, must be reckoned rather small, in terms at least of scientific progress. Indeed, his treatise was not a work of science, in the modern sense, at all: it proposed nothing that might be tested, it did not prove its case either in terms of observation or theory, and it made few conspicuous advances upon Ptolemy’s calculations. It is true that Copernicus was perhaps the first theorist since Aristarchus of Samos (c. 110–c. 130 b.c.) who had dared so openly to place the sun at the center of the “universe,” but his reasoning was more suppositious than empirical. He also devised a model that dealt somewhat more economically than the Ptolemaic with certain ancient questions, such as why Mercury and Venus remain always near the sun. This very problem had already prompted various reflective souls over the centuries to depart in their cosmological reflections from strict geocentrism: in the fourth century b.c. Heracleides Ponticus apparently claimed that Mercury and Venus revolve not directly around the earth but rather around the sun; the fifth-century encyclopedist Martianus Capella concurred (not on his own authority: he was not a scientist); and, in the ninth century, John Scotus Eriugena seems to have added Mars and Jupiter to the list of planets circling the sun. After Copernicus, in fact, Tycho Brahe (1546–1601) devised a system in which all the planets above revolve around the sun, while only the sun revolves directly around the earth; and by the time of Galileo’s trial, many of the greatest astronomers of the time (who were mostly to be found among the Jesuits) had come to conclude that the superterrestrial planets move in heliocentric orbits and had tended to adopt Tycho’s model (though they were willing to consider the Copernican, as an unproven hypothesis). 

Yet, for all the distinction Copernicus may deserve for having ventured a purely heliocentric description of the heavens, one should appreciate why his theory would not have been particularly compelling to all of his contemporaries. For one thing, the physical arguments he made were no great improvement upon those of the scholastics and so did no more than suggest that terrestrial movement is a conceptual possibility; and, for another thing, his mathematical model was wrong. Copernicus did manage to purge his system of equants, which his professors at the University of Krakow had taught him to disdain, but he still assumed, in good classical fashion, that heavenly revolutions must be circular (else they would not be “perfect”) and that the planets were fixed within separate spheres. Thus, in the end, he too was forced to resort to a system of epicycles—nearly fifty, in fact, including nine for the earth—with little appreciable advantage in predictive power over Ptolemy’s system. Tycho’s later model, it is arguable, is preferable as science, inasmuch as it better reconciles theory with the evidence. Tycho undertook (as Copernicus did not) minute investigations of the heavens, including an observation of a comet moving above the moon, where there were supposed to be only changeless planetary spheres. Moreover, one of the oldest objections to the idea of a moving earth was the absence of any observable alteration in the position of stars relative to one another (that is, “parallax” motion). Copernicus guessed that the distance between earth and the “sphere of the fixed stars” was far greater than was commonly assumed, but Tycho’s model offered a seemingly more plausible explanation. None of which detracts from Copernicus’s real achievements, such as they were, any more than it diminishes the far greater achievements of Galileo (1564–1642), Johannes Kepler (1571–1630), and Isaac Newton (1643–1727); but it does mean, certainly, that Copernicus was not some isolated visionary gazing back through the centuries, across a vast chasm of Christian darkness, to the pale flickering flame of a forgotten Hellenistic wisdom.

p. 61-62