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Organized contests in physics and mathematics have been around for a while: probably the most famous ones are the Mathematical Tripos at Cambridge; the Westinghouse and the Putnam in the United States; and the International Physics and Mathematics Olympiads. This post is about the correlation - or the lack thereof - between the winners list of these contests and the ranks of top scientists (e.g. signified by the Nobel prize or the Fields Medal). International Physics Olympiad : This is held for high school students. Many countries have their own national versions, which they use for selecting the team they send to the international contest. The test has both theoretical and experimental parts, each totaling five hours. Gold (top 8%), silver (top 25%) and bronze (top 50%) medals are awarded (everyone gets a certificate of participation). The IPO has been running since 1967, and counts 80 participating countries now, but not a single medalist has ever won the Nobel prize in physics. I should say though that a fair number of IPO medalists have become (non-Nobel-) distinguished physicists - a list can be found at the end of the webpage linked to the title of this subsection. What is the reason for the lack of correlation? Is it because the problems posed in the IPO are somehow 'artificial' (emphasizing quickness over depth in problem solving) and have little to do with substantial problems faced by real physicists which typically require deep thinking and a lot of time (interestingly, several Nobel laureates have helped and promoted the IPO - e.g. Leon Lederman, Alain Aspect and Ann L'Huillier)? Is it because winning the Nobel prize necessitates experimental validation and (sometimes) large scale collaborations? Is it because most IPO medalists who become physics professors have chosen to work in string theory (see the list), a field in which Nobels are not forthcoming? I don't know. International Math Olympiad : 6 problems have to be solved in 2 days, 4.5 hours per day allowed. The content is pre-university, calculus is avoided, calculators are banned. The topics are mostly algebra, geometry, combinatorics and number theory. Gold, silver and bronze medals are awarded roughly in the ratio 1:2:3. It started in 1959, now about 100 countries participate. Interestingly, tens of IMO medalists have won the Fields Medal in Mathematics. Some prominent examples include Terence Tao, Miriam Mirzakhani, Grigori Perlman (who declined it), and Akshay Venkatesh. Clearly, the correlation is much stronger than for physics. The reasons? I would love to know. Worth noting: physics Nobels are given many years after the discovery, Fields Medals are given before the awardees are 40 years of age; the Nobel prize is awarded every year, the Fields Medal once in 4. The Westinghouse/Intel/Regeneron : This is a prize for research carried out in high school. The outcome depends on many factors: a paper, essay(s), test scores, recommendation letters, academic performance in high school, etc. Started in 1942, limited to the US citizens and residents, about 2000 applicants annually. Westinghouse winners have accounted for 13 Nobel prizes and 2 Fields Medals. Not bad! The Putnam : A mathematics competition open to undergraduates in the US and Canada. 12 problems have to be solved over 6 hours on the first Saturday of December every year. Tests linear algebra, calculus and discrete mathematics. The Putnam Fellows get cash prizes. About 4000 students participate; the median score is typically 1/120. Archived problems can be found at the link. 2 Fellows ended up winning physics Nobels (Feynman and Ken Wilson) and 3 won the Fields Medal. A bit low, considering the competition has been running since 1938. The Tripos : Required for the bachelor's and master's degrees in mathematics at Cambridge. Started in the mid eighteenth century, and has evolved over time in its requirements. Intensive coaching was required for the exam. Those who received first class were called Wranglers and the position of Senior Wrangler has been called 'the greatest intellectual achievement attainable in England'. Some Famous Senior Wranglers: Cayley, Littlewood, Lord Rayleigh. Some famous Second Wranglers: Maxwell, Lord Kelvin, J. J. Thompson. A couple others: G. I. Taylor (5th Wrangler), Bertrand Russell (7th wrangler). Summary Contests like the IPO require intensive training, sharpen the mind, and stimulate creativity . I had a roommate in graduate school who had won silver at the IPO in 1993 and went on to his PhD at Harvard at the age of 19, and is now a professor at UCSD. He was clearly phenomenal. At the same time, I think in emphasizing problem-solving and answer-generation, IPO-type competitions miss a crucial aspect of physics research - nurturing the ability to pose deep questions. Some great scientists have indicated their ambivalence - if not outright distaste - for such competitions. I will conclude with two quotes that come to my mind. One is from the mathematician G. H. Hardy, who was sorry to have ended up 4th Wrangler, and thought that "although the race was ridiculous, he ought to have won it." The other is from Einstein (he failed his entrance exam to the ETH) who said he found consideration of any physics problem distasteful for a full year after graduating, because of the pressure of exams. Stuffing knowledge into himself, he said, destroyed his curiosity.

This post is a review of the book Sociobiology by the Harvard entomologist E. O. Wilson. It was originally published in 1975, to acclaim and controversy, and is considered a landmark work which established the biological and evolutionary basis of behavior in animals (including humans). It is about 700 pages long, and in spite of not being an expert in biology, I found it remarkably accessible. The book lays out in great detail, and with an abundance of examples, the author's thoughts about the genetic basis, and evolutionary modification, of social behavior. It is broadly divided into 3 main sections. Rather than tackle the impossible task of detailing the contents, I will give a general outline and mention the parts that stood out to me: Fundamentals : This part treats the basic factors behind the need for, and evolution of, social evolution. Wilson recognizes that the basis for existence of an organism is simply its role as a conveyor of its DNA (a modern, information-theoretic view considers DNA to be the software, which is refined by evolution, and our bodies to be the hardware, which is recycled ). And evolution has shaped our interactions - which occur through the emotions and instincts (love, hate, guilt, fear, desire, etc.) - to help perpetuate the organism during its lifetime with minimal damage to the DNA and maximal chances of propagating it. Therefore, the central problem of sociobiology, says Wilson, is the tradeoff - that every organism which does not live by itself has to negotiate - between selfishness (promotion of the self) and altruism (promotion of society). With this starting point, Wilson defines the units of society (e.g. individual, troop, band, population); and the kinds and degrees of sociality (e.g. permeability of status, amount of connectedness, direction of information flow). With these in place, he goes into the details of population dynamics (mating, birth, feeding, predation, cannibalism, disease, death, extinction) - there's a good number of mathematical equations here. Dynamics : This part gives details on the various kinds of interactions that prevail in a social system and their mechanics - e.g. communication; leadership and dominance hierarchies; parasitism, altruism and cooperation; courtship, sex and polygamy; parental care and division of labor; competition, territoriality and aggression (apparently there is an optimal level for each species); play, etc. Applications : This part starts by addressing the specific social behavior of bacteria and then successively moves through societies of insects, cold-blooded vertebrates (frogs and reptiles), birds, ungulates (hooved mammals) and elephants, carnivores, the nonhuman primates (monkeys and apes), finally making its way, in the final chapter, to humans. Surely a grand sweep! Wilson concludes that 4 groups have reached the peak of sociality: the colonial invertebrates (mosses and sponges), the social insects, the nonhuman primates, and human beings. However, he notes that the altruism and cooperativeness seem to go down as the complexity of the individual organism increases - doesn't put us on top of the list! It is actually the sponges, he says, which have evolved into nearly perfect societies. Summary This is a book conceived and written on a grand scale. I do not think it can be digested, even by a professional biologist, in one reading. It is a storehouse to which one can return repeatedly for information, understanding, and stimulation. Throughout the book, of course, are incredible examples from the extravagant beauty, terror, and diversity of nature: the fluidity of membership in chimpanzee groups (ex-members often kill present members and vice versa); the identification of seven different species of spiny lizards by their females (by the frequency and amplitude of head bobs); the differences in the human vocal apparatus, compared to the chimpanzees, that enable speech; the potty-training that tree shrews make their young go through... Wilson wrote (he passed in 2021) with clarity and culture, quoting at depth from the sciences, arts, literature, history and psychology with ease. He won two Pulitzers for his non fiction writing. This book is a grand sample of that legacy.

This post addresses misconceptions regarding the doctoral degree (I will stick to physics) that I have come across in a career of about 30 years in academia now. These misconceptions come from people both within and outside of academia. I find it remarkable how many myths and legends have grown up around this institution (they vary all over the place, and in some cases even contradict each other). A PhD is something you do if you cannot get a real job : PhD programs in physics are very competitive and have a high entry bar. It is unlikely that you will be able to get into one without solid credentials. A PhD should be an earth-shaking piece of work : There is no such requirement, and to go in with such an expectation might be naive. This is because progress in research is very challenging to make, and world-advancing advances in physics are made only once in a while. I have seen even very intelligent and capable people go in expecting the PhD to give them an almost mystical revelation and be disappointed if it does not happen. A PhD is the best piece of work you will do as a researcher : This rarely happens for people who go on to be researchers. The PhD is basically meant to train graduate students. So during a PhD they are basically in the process of being trained and their performance is likely not optimal yet. Further postdoctoral training (~5 years) is required before they become viable for faculty positions. About 5 more years are required before their position becomes permanent and they have the security (and other resources) to explore truly fundamental advances. So most people do their great work post-PhD. It is good to remember that although Einstein's thesis was outstanding (it was on Brownian motion and served to confirm the atomic hypothesis), it was not his best work (special and general relativity). An exception: John Martinis was a graduate student when he did Nobel-prize winning work that eventually got him to Stockholm in 2025. But of course it was his advisor (John Clarke shared + then postdoc Michel Devoret) who had the resources to set up the idea. A PhD on average has no impact : I feel this is one of the most dangerous misconceptions and it has been incorrectly opined by some eminent leaders of industry (ahem). For the reasons mentioned above, i.e. since scientific advance is difficult to make, clearly every PhD will not constitute a breakthrough. However, this does not mean it is not impactful. Theses are like drops in the ocean of knowledge: each drop is small, but without the drops there would be no ocean. More specifically, the overall advance of science depends on many small steps taken in the past. These steps are not always easy to trace, since science does not work linearly. Every good thesis is a stepping stone on which some large and imposing structure can eventually be built. Typically a thesis at a university is a part of a grant contract designed to fulfill a larger aim. These grants are in turn parts of well-considered programs which yield substantial scientific knowledge, which sometimes can also spin-off into impactful technologies. It is the patient work of many theses which generates the conditions for the perfect storm of the big scientific breakthrough. Finally, the impact on the person being trained should not be minimized. A quick look at industry, government and academia will reveal that a great many of the movers and shakers are holders of doctoral degrees. The PhD training is aimed at creating independent thinkers and problem solvers at a very high level. Whatever the impact of their thesis work in terms of specific science, they go on to make an impact on society based in their training. Example: Chemistry Nobel Prize winner Demys Hassabis has a PhD in cognitive neuroscience, and is now one of the leading AI inventors in the world, at Google. A PhD sentences you to a lifetime of poverty : On the contrary. Depending on which job your choose, you could be very well compensated. You need to be a genius to do a PhD : Persistence and enthusiasm are bigger requirements than outstanding intelligence. As I never tire of repeating, a Dean once told me that the PhD is awarded for stamina. PhD holders are elitists : The distribution of elitists among PhD holders is no different from that in the rest of the world. Once you have a PhD you will know everything about the subject : You will never know everything about the subject. Once you get a PhD, you are doomed to staying in academia : Industry and government agencies are filled with PhD physicists, not to speak of Wall Street and the finance industry, and of course other places. A PhD involves just more coursework than a master's degree : Some coursework will be involved, but the main requirement is original research. A PhD has to be completely original : Every thesis rests on work done before it, but also makes a substantial and original advance. A PhD overqualifies you : You need it if you want to become a professor (Masters will not work). Some industrial positions (team leaders) will need it. It may be an overqualification for some jobs. All PhD programs are the same : They may share some features in common (application procedures, graduation requirements, etc.). But they may have individual strengths (e.g. in certain disciplines). PhD advisors will guide you every step of the way : Not always, and perhaps this is an important enough topic that it deserves its own post later.

This post is a review of the book The Secrets of Soviet Cosmonauts by Maria Rosa Menzio (2022). The book gives insights into the Russian space program, starting from the launch of the Sputnik in 1957 that stunned the world, to the International Space Station. Many of the details, especially of the launch failures, had been classified for a long time. The main content of the book is centered around the following themes: Motivation : The book describes the main progenitors of the Russian space program: Prime Minister Nikita Khrushchev, aviation trainer Nikolai Kaminin (he was the one who selected Gagarin, and later pushed for a female cosmonaut), and aircraft designer Sergei Kovolev (forced by Stalin to live under an assumed name). Cosmodromes : There is discussion of the original Baikonur cosmodrome in Kazakhstan. Later launch sites include, Yasny, Morskoj Start [the only floating cosmodrome in the world (Musk has expressed his envy of it)] and Vostochny. Animals : At first the Russian program considered sending animals to space. Dogs were picked because monkeys misbehave. Laika (the name translates from Russian as "Little Barker") was the first living being sent into space, a month after the Sputnik (the book explains why she was female and what her reactions to the training were). Dogs Belka and Strelka were the first to be brought back alive from outer space, in 1960. Two turtles were sent into lunar orbit in 1968. Gagarin : The book gives the background of Gagarin and of his long and rigorous selection process; his five closest competitors (Titov, Volynov, Rafikov, Bondarenko and Nelyubov) are described. Gagarin became the first human being to go to space in 1961. He died in an aircrash (about which there are various conspiracy theories described in the book) at the young age of 34. Women : The next aim after getting a man into space was to send a woman. Interestingly, the communist system resulted in some equality for women - about 50% of engineering graduates in those years were female. Russia raced to send a woman into space, believing mistakenly that the US was close behind (they were 20 years behind). The book describes the finalists [Yorkina, Ponomareva, Solovyeva, Kuznetsova, Morozycheva, Popovich (called Madame MiG for her accomplishments as a test pilot), Savitskaya and Tereshkova]. Tereshkova's timeline is provided in great detail. Spacewalk : Alexei Leonov made the first spacewalk in 1964 (when I was young I enjoyed his book The Sun's Wind about the Soyuz-Apollo project; they docked in 1975). Afterword : The US landed on the moon in 1969. Russia is planning to land on the moon by 2030. The book has many details about the Soviet Union of the time. It gives interesting information about the Soviet space program as well Russian society. The English is colloquial and I found that made the reading fun. The technicalities are treated at a very accessible level. Overall an informative and enjoyable read!

This post is a review of the popular science book Haphazard Reality by H.B.G. Casimir , first published in 1983. Casimir was a well- known Dutch physicist who made notable contributions to both pure (Casimir effect, Casimir invariant, Gorter-Casimir model) as well as applied (as Director of the Research Lab at Philips) physics. I re-read the book after many years, on prodding from a colleague, while I was visiting the Netherlands over the last two weeks. Casimir's memoir is about his experiences in science and is valuable because he was in the thick of the action as quantum physics was being developed in early twentieth century Europe; and because he later moved to industrial research which had became important in the WWII years. Casimir had an early start in life. His parents were both educators, fostered Casimir's curiosity, and made sure he received a very good education. Ehrenfest, who was professor of theoretical physics at Leiden, was a family friend, and eventually took Casimir on and gave him a PhD when he was merely 22 (during this time Casimir describes his interactions with Goudsmit and Uhlenbeck, who were students of Ehrenfest and established the existence of electron spin). Casimir also gives a detailed professional as well as personal account of Ehrenfest (who was Boltzmann's student), touched with admiration for his advisor, but also frank in the analysis of the causes of his eventual suicide (apparently the person most aware of the situation had been Dirac). During this time, he attended seminars delivered by Planck, Einstein and Pauli and other distinguished scientists. Casimir's first postdoc was with Bohr (Ehrenfest introduced Casimir to Bohr saying ' He can do something, but he still needs a good thrashing '), and his account of Copenhagen refers to amusing places like the Cafe Antiautomat (set up as a protest against vending machines); to Bohr's preference for completing papers on Saturday (so the postal travel wasted only Sunday, not a workday); to watching Western movies with Bohr, Gamow and Landau (Bohr proposed a gunslinger effect positing that a willed movement is slower than an automatic reaction, implying that the person who is the later to draw in a gunfight is likely to win; Casimir provides a poem commemorating the theory). There is also an amusing Bohr story about identical twins (one of whom is sent to Harvard and the other to Yale) - but one has to read the book. Casimir's second postdoc was with Pauli in Zurich, where he discovered upon arrival that church clocks in Switzerland were not quite synchronized. There are mentions of visits by Bhabha, of Pauli's friendship with Jung, and of Pauli's drunk driving. Later, in response to his stubbornness in argument, Pauli called Casimir a Stehaufmanderl , in reference to a toy which always returns to the vertical (because its center of gravity is so low). Casimir was next recalled to Leiden by Ehrenfest so he could take charge of the theoretical physics division; he read about Ehrenfest's suicide while on the train from Copenhagen: the moves had likely been planned in advance. Leiden University made Casimir a professor at 30, but he did not believe himself to be a top notch theoretical physicist, and was relieved to be relieved (sic!) by the distinguished Kramers . I knew about Kramer's work in physics; the book reveals that he translated Mallarme , played the cello, and introduced Casimir to Tristram Shandy . Casimir describes other giants of physics, such as Lorentz, whom he met only once. He gives a perceptive account of the scientist, who was remarkable in being both a 'classical' and a 'modern' physicist at the same time. This in the sense that he came from a pre-relativity and pre-quantum tradition of physicists, but remained in touch with developments so he did not become obsolete at any point in his career. Lorentz is often thought of as the main bridge between Maxwell on the one hand and Einstein and Bohr on the other. Another person Casimir describes in some detail is Kammerlingh Onnes (KO), who discovered superconductivity at Leiden. Casimir regards KO as a pioneer, but criticizes his social prejudices (class conscious) as well as scientific administration (dictatorial). There is a long chapter on WWII, describing the German occupation, after which Casimir chose to move to Philips. His stay in industry involved the development of many devices (radios, cyclotrons, etc.) and the interaction between fundamental science and technology, which he describes at length (he points out that scientists are often the first users of new technology, while technology takes some time to use the latest results in science). Overall, his insistence is on academic freedom for research, both in universities and in industry. Some more interesting facts I learnt from the book: After the war, Casimir was courted by universities abroad, including Rochester (which had recently lost Weisskopf). In 1807, the University of Leiden had finally been able to expand when a barge carrying gunpowder and moored near campus accidentally (?) exploded and gutted about 500 houses. Casimir was responsible for persuading B. G. Escher (M.C. Escher's half-brother) to teach crystallography at Leiden. Summary : An interesting read, covering the physics of the 1930s (there are two extensive appendices with Casimir's viewpoints on this era), from the pen of someone who was rather close to the central actors.

The last two weeks I have been traveling in the Netherlands, for the first time. I stayed in Amsterdam and visited several places about an hour by train. A few places I went to: Amsterdam : Lots of canals, as is well known. I went to the Anne Frank house (turned out to have the same street number as my dorm room in college), the Hotel Pulitzer with a grand piano hanging from the ceiling above the entrance, the van Gogh museum, the Rijksmuseum [which had exhibitions on armoury including a six foot long rifle; Rembrandt's Nightwatch undergoing restoration; a bunch of Vermeers and Ruisdaels; and the biggest diamond (the Banjarmasin ) that I have seen in my life]. In the vicinity was the MOCO (Museum of Contemporary Art) with modernists like Keith Haring and the street artist Banksy , whose imaginative work I enjoyed quite a bit. Close by is the beautiful Vondelpark , a fine place to take a post-lunch walk. Finally, I went to the Rembrandthuis (house of Rembrandt). The original kitchen, bedroom, studio, it's all there. As impressive as the paintings were the copper etchings; no one could paint human eyes like Rembrandt, the light in them almost unearthly, the crinkles around them showing age and character. There is a special term used to describe the type of portraits he made: they are called 'tronies'. Tronie is Dutch for face. A tronie painting aims at revealing an exaggerated mood, rather than achieving a likeness of the sitter, who was often anonymous. Leiden : A small town with a famous university. The Nobel prizes for superconductivity (Kammerlingh Onnes) and magnetism (Zeeman and Lorentz) have placards associated with them outside the physics department. I also learned the only siblings (talk about sibling rivalry) to ever win the Nobel were from Leiden U - Jan (Economics 1969) and Nikolaas (Physiology/Medicine 1973) Tinbergen. I will mention something more about the university in my next post. Opposite the physics department is the Wereldmuseum (the National Museum of Ethnology) where my mother got a masters degree back in 1964. Compact collection of Chinese, Indian, African, Latin American and Middle Eastern art. The most interesting exhibit was focused on the peoples of the Arctic; second prize goes to an extensive display on K-pop. Rotterdam : The attractions include the Erasmus bridge , which one crosses to see the Hotel New York, which served as a boarding house for immigrants to the US who sailed the Holland-America line, specifically the SS Rotterdam (now permanently moored in the harbor) to Ellis Island. The most famous passenger to take this route: Albert Einstein. There's a Museum of Immigration near the pier which gives a lot of background to those voyages. A nice eating place downtown: the artistically done Markthal , which in turn is close to the famous cube housing . The Euromast tower provides a panoramic view of the whole city, somewhat derailed by fog when I visited. Den Haag : The seat of the government. The Mauritshuis has some very fine Dutch paintings (in particular the Vermeers are outstanding - including, but not limited to, the Girl with a Pearl Earring , another tronie, and sometimes called the Dutch Mona Lisa ). There is a museum celebrating the famous graphic artist Escher , beloved of physicists and mathematicians - got to see his handwritten journal, and learn that his half-brother was a professor of crystallography (relevant to Escher's famous work on tiling). A very entertaining visit was to Madurodam , a miniaturized model city, representing the main architecture from various cities (Erasmus Bridge, the Dom Tower, the Markthal, Schiphol airport, canals with automated boats, roads with automated traffic, rail tracks with automated trains), industries (shipping, windmills), etc. Check out the famous Sand Castle building. Utrecht : The museum Speelklok : A very impressive collection of musical machines - street organs, dance machines (some of them as big as a house), musical time pieces, self-playing pianos; everything that came shortly before Edison's phonograph (which rendered them obsolete). Some of the machines looked like the early computers, with the melodies encoded on metal discs or cylinders or punched hole paper cards. Other attractions; the Dom Tower (the highest tower in the Netherlands); the Scheveningen beach on the North Sea; the Kunstmuseum, with a lot of information on the Titanic, including part of a scale model. Haarlem : The Frans Haals Museum has a fine collection of paintings. The Teylers Museum (the oldest in the Netherlands) has an extensive (with ~18,000 exhibits) and outstanding collection of historical scientific instruments - electroscopes, microscopes, telescopes, magnets, vacuum apparatus, electrostatic generators (as big as a room - one can only imagine the sparks generated), and many more. Lorentz apparently had a lab here, which Einstein visited. Afterword : Visiting the Netherlands in the winter has its pros and cons: the temperatures can be quite low (~30F), but the touristic rush is much less (especially in the museums). A warning: beware of the bicyclists when you walk around, they come at you from every direction. The Dutch are friendly and direct; almost everybody speaks English. Other places to visit on a later trip: Delft, Eindhoven, and Maastricht.

This is a review of the book This Is For Everyone by Tim Berners-Lee . Berners-Lee invented the World Wide Web, which has, of course, completely revolutionized our lives. This book is his own account of the origin and development of the web. I was particularly fascinated by it as my generation saw the web come up in our own lifetime - I remember in 1995 the librarian at the University of Rochester asking my incoming graduate class in physics to indicate by show of hands how many of us had ever used the web. In the book, Berner-Lee's autobiographical details are interspersed with the narrative, but for this review I would like to tease them apart. Bio : Berners-Lee talks about his unusual family background. Both his parents were electronic engineers. They encouraged young Tim to be a nerd (particularly notable, I thought, was the fact that the center of family attention was not the TV but the Encyclopedia Brittannica). Young Tim eventually assembled his own computer. Alan Turing was a family friend. Berners-Lee had very good high school teachers. Then he went to Oxford for his bachelor's degree. He worked in a couple of technology companies before he joined CERN, perhaps a place ideal for his epoch-making invention: CERN experiments were producing a large amount of data, which needed computer analysis; CERN had the money to buy a large variety of computers to train on - mainframes, workstations, microprocessors; CERN was a large organization, a natural place to start thinking about how to connect people so they can share computerized information. Later, he relocated to the US (MIT), moving the center-of-gravity of the web to America. His various awards (most notably a knighthood and the Turning prize) and three marriages are worked into the largely technical narrative. WWW : Berner-Lee's pioneering idea was to combine the internet, which already existed at that time, with hypertext (computer text with clickable links to other text). He made the first web browsers (clients), and web servers (which hosted webpages). The book talks about the early days of TCP/IP (the method of shooting data packets over the internet); email; FTP (hey I used the File Transfer Protocol in college!) and its eventual replacement by HTTP (this is the language that enables our browser to receive web pages from web servers); Berner-Lee's crucial use of Steve Jobs' NeXT computer to write his web code; his incorporation of the DNS system, his invention of the URL (a unique address for any resource on the internet; a name Berners-Lee did not like, incidentally). Of course, the usual suspects of the story appear in the book: Vannevar Bush (one of the visionaries of hyperlinking), Vint Cerf and Bob Kahn (the originators of TCP/IP), Gates and Jobs, Douglas Engelbart (who invented the computer mouse) and The Mother of All Demos , Hakon Lie (CSS for anyone who has ever designed a webpage), Guido van Rossum (who invented Python), Larry Page and Sergei Brin, Jeff Bezos, Mark Zuckerberg, Demis Hassabis and many more. Themes that permeate the book include Berner-Lee's preoccupation with the user's personal control of their data, and open sourcing as much of the code development as possible. AI is another preoccupation. Thoughts about this include early but unfulfilled aspirations, the eventual rise of OpenAI, and concerns about where the field is going. A third prominent theme is the use of the web for promoting societal well-being (thoughts on social media are included) and what he calls intercreativity (group creativity - he gives Wikipedia as an ideal example). Summary The book is useful as a the personal take of the creator of one of the greatest inventions of all time. Berner-Lee's background, temperament, motivations and philosophy shine through the writing. His interactions with the pioneers give insights into the history of and motivation behind of the internet. For the bookshelf of the scientist, technologist or even layperson, I would say this book is an indispensable item.

One of the saddest sights in all of science is that of an expert whose interests have become so narrowed by their field of specialization that they regard everything else as irrelevant and an intellectual nuisance. An extreme manifestation of this is the bias that in their view, what they are researching is the only worthwhile intellectual goal, and everybody else is wasting their time. In this context I am reminded of a limerick about Benjamin Jowett, a famous professor of Greek at Oxford: My name is Benjamin Jowett I am Master of Balliol College Whatever is knowledge I know it And what I don't know isn't knowledge In fact, this kind of chauvinism is a common human trait, and can be observed in every field of human endeavor. I have met musicians who loudly proclaim their tradition to be the oldest and finest (or the newest and most modern); martial artists whose gambit is that their style is the only one that teaches proper punching or kicking; dancers who announce their genre is the best partnering style, and so on. While this attitude is not admissible in any field, it is particularly galling to find it in science, which is supposed to be impassionate and unbiased. I believe this kind myopia can be traced to two sources. First is the containment within atomized disciplines and lack of regular exposure to other people's work. This is like not traveling to other countries - one starts developing unfounded biases about how these other places run and the kind of people that inhabit them. Visiting the countries completely changes our opinions. This is why travel is a - necessary - form of education. An acceptable substitute is reading. The second is the natural human tendency to claim superior ground by association. I may not be as good a scientist as Fermat or Euler or Gauss, but I can claim distinction by association by announcing that I 'only do number theory'. I have nothing against people who do number theory - they are fantastic, I am sure, and the field certainly is; I have great admiration for it. My only objection arises when people use their association with fields like number theory to claim superiority over other, perhaps more applied, branches of mathematics, say like hydrodynamics. The truth, of course, is that every field has its own beauty as well as use. Even in applications and experiments there is great art and beauty. Just look at the cell phone in our hands - what a marvelous construction. Moreover, if we examine the careers of the great scientists, we find they had no qualms about working in multiple (pure as well as applied) disciplines. Gauss made pioneering contributions to geodesy; Lagrange worked in ballistics; Fermi made the first nuclear reactor; von Neumann, Bethe, Feynman, Mandelstam and Oppenheimer worked on the bomb; Dirac participated in isotope separation; Einstein came up with torpedo designs. The examples are actually endless. In my career I have learned to be wary of such 'experts'. They are useful, but a common problem is that they are not good at realizing their own limitations (the good ones do, of course). I have also found that people who go around posing as intellectual superiors are usually not very creative or productive. Not having down to earth accomplishments, they therefore they find it necessary to bask in reflected glory. To me, a topologist who has not published anything very original in twenty years does not carry much weight compared to an applied scientist who has moved the needle substantially in fuel cell technology (even though I think topology is a magnificent topic). In this context I find it useful to remind myself of a quote a colleague gave me a long time ago: "I don't judge people by what they are doing; I judge people by what they have done."

This post is a brief review of the book Don't Be Afraid of Physics by Ross Barett and Pier Paolo Delsanto. The subtitle is Quantum Mechanics, Relativity and Cosmology for Everyone . In the introduction, Nicola Maria Pugno suggests that the book is appropriate as a textbook for courses of science for college students majoring in a non-scientific field. I agree, with the perhaps obvious observation that the audience can be extended to people who have ever been to college. There is one formula in the whole book, keeping in mind the warning Stephen Hawking had received when he was writing a Brief History of Time: every formula would reduce book sales by half. First third : I found it interesting that a substantial part of the book (the initial third) is occupied by what science is, rather than starting with the historical recounting of inventions and discoveries. The discussion starts with the use of some optical illusions to show that our senses cannot be fully trusted, and we need science to takes us beyond what our senses reveal to us about the world. The steps then take us from Aristotle to Galileo to Planck (a lovely rant from him about how his work on quantum mechanics was initially ignored by the scientific community). This is followed by a chapter discussing the issues of intelligence, logic, understanding, complexity (with some jokes about mathematicians, which can be appreciated by physicists); a chapter discussing truth (including Occam's razor), beauty and the role of faith in the scientific endeavor. The last chapter in this section addresses Godel's theorem and Hawking's work on black holes. Second Third : This was the more expected part of the narrative for me. The first chapter in this section focuses on quantum mechanics, the Hesienberg Uncertainty Principle, the collapse of the wavefunction, interference, entanglement, Schrodinger's cat. The next two chapters deal with special (simultaneity, length contraction) and general (the principle of equivalence, gravitational lensing, black holes) relativity. The following chapters expose particle physics (as revealed by accelerators) and modern cosmology (as revealed by modern telescopes). The last chapter contains more modern concerns in cosmology, such as dark matter and energy, hyperspace, wormholes, and inflation. Third third : This part deals with open questions at the frontier of science. There are discussions about larger quantum mechanical superpositions involving living organisms (at the interface of physics and biology), the multiverse, and the ultimate nature of space and time. Summary : This is an informative, entertaining and accessible book. The physical and philosophical details are interlaced with lots of anecdotes, asides, and images. I would recommend it for both scientists (they might enjoy learning about the Monty Hall problem , as I did ) and non-scientists. Caveat: The topics selected probably reflect the author's concerns as researchers. There is nothing about lasers, semiconductors or superconductors in the book. Or much of any applications of physics.

This is a review of the The Strangest Man by Graham Farmelo . It is the biography of Paul Dirac, one of the pioneers of quantum physics, the youngest ever theoretical physicist to win the Nobel prize (at 31 years of age), and according to Stephen Hawking, the greatest English physicist since Newton (I would place Maxwell and Faraday as close competitors for the accolade). The book is deeply researched and well written and has won several prizes, including the L.A. Times Book Prize for Science and Technology. It is a substantial (~540 pages) treatment of the life of the man who was famous both for his intellectual achievements as well as his eccentricities (stories about him abound; some of them will be recounted below). The title of the book derives from a quote by the famous physicist Bohr, who was one of Dirac's mentors. Rather than follow the chronological presentation of the book, I will describe the major themes around which the author writes: Dirac's relationship with his father : His father was domineering and disciplinarian. Dirac famously became taciturn because his father would only allow him to speak French at home, with penalties for every mistake Dirac made. His father was not affectionate and did not allow Dirac visitors. His father's relationship with his mother was volatile and made home a toxic place for Dirac. Later, Dirac thought better of his father as he received financial support for his academic career from him. But even later, it became clear that the money had come from elsewhere, and that Dirac's father had simply taken the credit for supplying it. Dirac spoke little, was socially awkward, and did not prefer to collaborate professionally. A famous example, included in the book: At a talk he was giving, someone from the audience said he had not understood such-and-such point. Dirac remained silent. After some prodding from the host to answer the question, Dirac responded that it was a statement, not a question. Because he was also very logical, Dirac's brevity of speech produced entertaining stories, some probably apocryphal. One that I did not find in the book (or missed): He was traveling via train with a friend who looked out into the English countryside and observed that the sheep seemed to have been sheared. "At least on this side," replied Dirac. Dirac's insistence on mathematical beauty : Dirac famously insisted that in physics truth was to be found by searching for equations that were beautiful, rather than by trying to model experiments. Even approximate theories he said, can, and should, have mathematical beauty. There has been a lot of discussion about these assertions and even entire books refuting them. The biography returns time and again to this theme, starting, as far back as the curricular influences of the Aesthetic Movement in England in the 1850s. It goes on to describe the role played by mathematical aesthetics in Dirac's thinking as he cut his teeth on his initial training, then performed his groundbreaking work in the face of competition from European colleagues, and was finally superseded by advances made by younger, largely American, physicists. Dirac's theoretical brilliance : Dirac's theoretical brilliance manifested itself clearly in high school. He digested both special and general relativity by himself as an engineering undergraduate. In his professional career, by employing pure thought, he managed to make astonishingly deep advances in physics. There are extensive descriptions in the book of his interactions with major scientists in Cambridge and elsewhere (Rutherford, Bohr, Einstein, Schrodinger, Heisenberg, Pauli...and of course Fowler, his thesis advisor) and the great regard in which they held him. An undesirable side effect of his academic brilliance was his discord with his brother, who was not as bright, felt overshadowed, and eventually committed suicide. Dirac's connection to communism : Dirac was greatly interested in the Soviet Union, visited it, and had a particularly close friendship with his Russian colleague at Cambridge, Pyotr Kapitza. The book covers this aspect with wartime and postwar Europe as the background. As a result of his Soviet connections, Dirac was initially refused a visa by the United States. This resulted in a visit to India. Perhaps it would be relevant to mention in this section that Dirac was also quite atheistic. He was vocal about his (lack of) belief and this led Pauli to famously and sarcastically say (as reported in the book) that there is no God and Dirac is his prophet. Dirac's antireligiosity led to some difficulty in securing a gravestone at the Westminster Abbey, an honor accorded only to the greatest of British subjects. Persistent lobbying by the physics community finally succeeded in getting him admitted (at least 10 years have to pass after death for the honor to be considered) in 1995: today his stone decorates the Abbey floor, inscribed with his famous equation (I visited it in 2022). Dirac himself lies buried in Florida. Summary Overall, the book rings true and deserves all the accolades it has received. It is good to finally have a substantial biography of one of the great figures of 20th century science. The technical matter has been conveyed very well and should be largely accessible to a layperson. Although Dirac's presence is still substantial in the physics lore, I still learnt some things from the book that I did not know: Dirac's text was Einstein's preferred book on quantum mechanics; Dirac had a sense of humor which extended to mailing a baby alligator (while he was working in Florida) to the physicist Gamow; Dirac liked entertainment and art, including Mickey Mouse and Cher, Sherlock Holmes and Dali. Perhaps the most moving episode in the book is a remarkable conversation with the physicist Pierre Ramond in which Dirac claimed his life had been a failure, since modern quantum theories, though they matched experiment, were not elegant enough for his taste.

In the spirit of Thanksgiving, a thanks to the readers of this blog : Thanks to the readers of this blog For staying with me thus far (Some of you now probably are Enjoying turkey and eggnog) In a month this blog will complete Three years (a hundred and fifty Posts). As a milestone that's nifty I thank the readers for this feat The book reviews are read the most I enjoy writing them as well I think if I can help books sell Then it was worth writing the posts The Nobel Prize articles score Large hits also, and an eclipse Esp. if I include viewing tips Attracts a hundred reads or more Black holes never fail to attract Readers. It must be gravity That pulls them. Even naivete Cannot contradict such a fact The blog helps me gather my thoughts On a topic once and for all And reference them, spring or fall When required, to connect the dots Where else to collect acronyms That sound cool; commemorate The giants of science; enumerate Issues according to my whims? Where else to send the students who Each need to be told the same things Without repeating myself? Links To posts are now sent to each: whoo! Where else to broadcast to the world Interesting Stories from Science Cool experiments; new designs For theories; div, grad and curl ? So thanks to the readers once more For their support of this platform Enjoy the holidays, stay warm Then join me for year number four!

This post is about Occam's razor, i.e. the statement, that when presented with competing explanations for the same phenomenon, the one with the fewest assumptions is likely the correct one. It is often used prescriptively in its abbreviated form - "Choose the simplest explanation." Occam's razor is not a law, it is a rule of thumb. It is often useful and leads to the right answer. This post is about some major exceptions to the statement. I wrote it because I find people often use Occam's razor as if it is a law (rather than a heuristic). Doing so can lead to flat mistakes (mainly because of overemphasis on simplicity), something every researcher and indeed human being should be aware of. Carelessness in using Occam's - or anyone's - razor can result in shaving off parts that are actually critical. Physics : There are many examples. I will mention a few. a) Cosmology : It is simpler to assume that the Earth, rather than any other heavenly body, is the center of the universe. In fact it was possible at one time, to explain the observed motion of the heavens quite well using that assumption. Nonetheless, it is not correct. Another example was the observation of perturbations in the orbit of Mercury. Simplest explanation as per Newtonian dynamics? The presence of a nearby planet. But no one found such a planet. Mercury's behavior was later explained by Einstein's theory of general relativity: a more complicated explanation. Yet another example: the steady state model of the universe is simpler than the big bang model. For a long time it was consistent with the observed data. But it is wrong. b) Thermodynamics : The phlogiston theory assumed there was fire inside every combustible object, which was merely released on burning. Lavoisier proved this simple theory wrong by demonstrating weight gain during burning and the crucial role of oxygen in the process. Ergo: the real explanation was much more complicated. c) Atoms : Scientists like Mach (opposing Boltzmann, among others) argued there was no need to postulate the existence of atoms, since physical and chemical laws known at the time could be described without them. 'nuf said. d) Neutrino :  In the case of radioactive (beta) decay, the simplest explanation was a violation of the law of conservation of energy. The more complex, but real answer: the existence of a completely new particle, the neutrino, which carried away the missing energy. Confirmed by experiment (1995 Physics Nobel). e) The standard model : The best, experimentally confirmed, working theory we have of the universe seems to be complicated and ad hoc . It is hard to argue that it is simple in any sense. Geology : The theory of continental drift was initially thought as too complex an explanation for the observed distribution of biological species. Turns out to be right, though. Mathematics : One example from pure, and another from applied, math. a) Non-Euclidean geometry : Two parallel lines only meet at infinity, says Euclid's 5th proposition. After many centuries, Bolyai, Lobachevsky and others showed this was not true for non-Euclidean geometries. A relevant example is Riemannian geometry, which provides the framework for Einstein's theory of gravitation. b) AI : Occam's razor fails spectacularly here. Reality is complex. That's we need large language models for learning it. In machine learning complex models are easier to train than simple models. Biology: This is a field where Occam's razor, as Crick pointed out, is especially dangerous to use (because natural selection does not always pick simple or minimalistic solutions). a) DNA : DNA (which has only 4 nucleotides) was not considered seriously as the vehicle for genetic transmission in contrast to proteins (which have 20 amino acids) for a long time. Here the razor worked in reverse - DNA was thought to be too simple to be the answer to life. b) Stomach ulcers :  Simplest explanation? Stress and excess stomach acid. The more complex, but correct, explanation, involves the bacterium  Helicobacter pylori . Barry Marshall and Robin Warren got the 2005 Nobel for finding the right answer. Afterword I do not advocate against the careful use of Occam's razor. It is a useful but crude tool. Unthinking use of it can represent intellectual laziness. It would probably be good to keep in mind Einstein's warning: "Everything should be as simple as possible, but not simpler." And it is also good to remember that what is simple is actually a subjective opinion. Thus also Oscar Wilde: "The truth is rarely pure, and never simple."