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Professor Kleiner features the architecture of Augustus' successors, the Julio-Claudian emperors, whose dynasty lasted half a century (A.D. 14-68). She first presents Tiberius' magnificent Villa Jovis on the Island of Capri and an underground basilica in Rome used by members of a secret Neo-Pythagorean cult. She then turns to the eccentric architecture of Claudius, a return to masonry building techniques and a unique combination of finishe...more
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In this lecture, Professor Kagan examines the continuation of Spartan tyranny over the Greek poleis and the response of the Greek world. According to Professor Kagan, it became clear that the Greek poleis needed to do something to check the power of Sparta. So, Thebes, Argos, Corinth, and Athens along with some of the smaller poleis joined together to fight Sparta in the Corinthian War. The war ended in a stalemate, but now the Persi...more
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Musk talks about the problems with space exploration in the US in the 22nd century. The long term plans are to have something cheaper and safer. In Russia, it is safer and cheaper and they have a better track record. They are constrained however by the weakness of the Russian economy. China is expected to launch their first person into space this month, becoming the third country to put a person into the orbit. They have great ambitions an...more
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After showing how a double-minimum potential generates one-dimensional bonding, Professor McBride moves on to multi-dimensional wave functions. Solving Schrödinger's three-dimensional differential equation might have been daunting, but it was not, because the necessary formulas had been worked out more than a century earlier in connection with acoustics. Acoustical "Chladni" figures show how nodal patterns relate to frequencies. The analog...more
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If the early years of the twentieth century were marked by a general consensus that a major war was impending, no similar consensus existed concerning the likely form that war would take. Not only the carnage of World War I, but also the nature of its alliances would have been difficult to imagine. Indeed, in 1900 many people would have predicted conflict, rather than collaboration, between France and Britain. The reasons for the eventual ...more
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It is important that chemists agree on notation and nomenclature in order to communicate molecular constitution and configuration. It is best when a diagram is as faithful as possible to the 3-dimensional shape of a molecule, but the conventional Fischer projection, which has been indispensable in understanding sugar configurations for over a century, involves highly distorted bonds. Ambiguity in diagrams or words has led to multibillion-d...more
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This lecture traces the development of elemental analysis as a technique for the determination of the composition of organic compounds beginning with Lavoisier's early combustion and fermentation experiments, which showed a new, if naïve, attitude toward handling experimental data. Dalton's atomic theory was consistent with the empirical laws of definite, equivalent, and multiple proportions. The basis of our current notation and of precis...more
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Half a century before direct experimental observation became possible, most structures of organic molecules were assigned by inspired guessing based on plausibility. But Wilhelm Körner developed a strictly logical system for proving the structure of benzene and its derivatives based on isomer counting and chemical transformation. His proof that the six hydrogen positions in benzene are equivalent is the outstanding example of this chemical...more
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Why ethane has a rotational barrier is still debatable. Analyzing conformational and configurational stereotopicity relationships among constitutionally equivalent groups reveals a subtle discrimination in enzyme reactions. When Baeyer suggested strain-induced reactivity due to distorting bond angles away from those in an ideal tetrahedron, he assumed that the cyclohexane ring is flat. He was soon corrected by clever Sachse, but Sachse's w...more
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Roberts believes that with increasing use of the internet, television and mobile phones, the consumer is moving from early adoption to mainstream consumption. The customer has high expectations of new products and wants to influence technology. Venture capitalists choose to invest in companies that embrace the trends of new and younger consumers.
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By 1950, in most of the underdeveloped world, mortality had fallen to about half its pre-modern rate. The birth rate, however, had remained high and, by 1950, was about twice the death rate. For the rest of the century, both rates fell dramatically and in parallel, maintaining the gap. The enormous excess of births over deaths in this period is known as 'the population explosion.' By 1990, the world population was growing at almost 90 mill...more
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The boom in European colonial expansion in the second half of the nineteenth century, the so-called New Imperialism, can be seen to follow from three principle factors, in ascending order of importance: religious proselytizing, profit, and inter-imperial political strategy. With respect to the latter concern, the conflicts emerging from imperialism set the stage for World War I. Along with its military and industrial consequences, imperial...more
