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In September of 1959, the arriving Freshman Class of 1963 was treated to a few interesting lectures. One was by the famous mathematian Norbert Wiener (called "the father of cybernetics"), and another was a fascinating lecture on color vision by Edwin Land, the founder of Polaroid.
But when both projectors were uncovered, we were startled to see a full-color image on the screen! The colors were not highly saturated - that is, they seemed a bit "washed out". Nevertheless, the full spectrum of colors was present, in complete contradiction to conventional color theory. Somehow, our brains had managed to assemble an approximation of the colors in the original scene. This work had been reported in a 1959 article in Scientific American, and Land later developed what he called his "Retinex Theory of Color Vision". Note 1 The lecture was a fascinating introduction to MIT.
Every student at MIT knew Professor Wiener by sight. He was the prototypical brilliant absent-minded professor. A classified 1942 monograph on signal transmission in a noisy environment was nicknamed "the yellow peril", because of the color of the cover and because few people could understand it. He wrote a book about his childhood called "Ex-prodigy". There are many stories about Wiener at MIT available on the web, so I won't repeat them here. Note 2 Just do a search on the terms ["norbert wiener" stories]. But I should caution you that they are not all true. In particular, the one about his not recognizing one of his own daughters was denied by his daughter Peggy Wiener Kennedy, who said, "Father may have been absent-minded, but he always knew who we were." Note 3 Back to Rota's lecture hall. Rota announced, "Professor Wiener will give today's lecture", and stood aside. Wiener lectured us on some obscure mathematical topic that had absolutely nothing at all to do with our class material. After receiving applause at the conclusion of his lecture, Wiener lit a cigar, and toddled off down the hall. Rota never said a word about why Wiener had been invited to lecture. But Wiener was getting on in years, and I imagine that Rota wanted all his students to hear the great Professor Wiener speak. Wiener died a few years later, in 1964.
I recall Shannon once describing how he was converting an old school bus into a camper for his family. In order to better visualize good ways of arranging the interior, he built a scale model of the bus. Its top could be removed, allowing him to experiment with various layouts of the interior partitions. Once the actual bus had been fully outfitted, he put the scale model bus on its kitchen table. However, this created an innaccuracy that disturbed him. So he bought a very small toy bus, and placed it on the kitchen table of the scale model bus. With a twinkle in his eye, Shannon then said to us, "And inside that toy bus, on the kitchen table, theoretically ..."
Upon arriving, I could immediately see that some of the audience members were not MIT students. Although they were fairly young, they were dressed in expensive three-piece suits. I sat next to some of them, so I could hear what they were talking about, to try to figure out who they were. They turned out to have been sent to the lecture by various New York brokerage firms, who had evidently seen the Tech Talk announcement, and wanted to see if Shannon's research was anything useful. As the lecture started, they all took pads of paper out of their leather attaché cases, so they could take notes to bring back to their firms. The trouble was, Shannon immediately began filling the blackboards with differential equations. I watched as the brokers' jaws dropped. They seemed unable to even take notes to be interepreted later - all the boards were covered with integrals and summation signs and Greek letters that they didn't even know how to copy accurately. I wondered how their reports would go over back in New York. Note 5
From 1961 through 1966, Charles Townes was Provost of MIT. Some time during that period, I saw an item in Tech Talk announcing a lecture at MIT by Dennis Gabor. I arrived early, and sat in the front row. Gabor was waiting at the front of the room to start his talk, when another early arrival showed up - Charles Townes. Townes introduced himself to Gabor - I got the impression they had never before met. They shook hands right in front of me - the inventor of the hologram, and the man who had invented the laser which had turned his theoretical invention into a reality. Townes won the Nobel prize in physics in 1964 (shared with Nikolay Basov and Alexander Prokhorov). Later, in 1971, Gabor would be awarded the Nobel prize in physics for his work on holography. Note 6
Some time later, another student asked me whether I had had the good fortune to see the artist, Alexander Calder. For that was indeed who it had been. After checking out the work and pronouncing himself satisfied with the installation, Calder had been signing it as I passed by, using a welding torch to create a raised signature on the steel. The photograph to the right shows a close-up of his signature. ![]() ![]() Note 1: An interesting description of Land's accidental discovery of this effect can be found here. [return to text] Note 2: OK, here's what I've always thought of as the best of the stories. Back when Wiener actually had to teach Freshman math courses, a student asked him how to solve a particular problem that had been assigned for homework. Wiener read the problem, wrinkled his brow for a few minutes, and, having solved it in his head, wrote the answer on the blackboard in the front of the room. This was no help to the student, of course. But not wanting to insult the famous professor, the student cagily asked if there was another way to solve the problem. Wiener thought this was an interesting question, mumbled to himself a bit, paced back and forth for a while, and then again wrote an answer on the blackboard. Seeing that it matched the first answer, he smiled with satisfaction. At this point, the story goes, another student at the back of the classroom said, "Professor Wiener, I've got a third way to solve the problem." Wiener allowed as he didn't see any other way to go about it. The student held his head in his hands, paced rapidly back and forth for a while, and then wrote the same answer on the blackboard at the rear of the classroom (many MIT classrooms had blackboards both at the front and the back of the room, so you were less likely to run out of space to write). The class laughed, but in the front of the room, Wiener was shaking his head from side to side. "What's wrong?", asked the student. "I got the right answer, didn't I?" Wiener replied, "Oh, you got the right answer, all right, but your method was all wrong." I should say that the two times I heard Wiener speak, he had no problem bringing himself down to the level of his audience, and making himself perfectly clear. [return to text] Note 3: Jennings, Karla. The Devouring Fungus: Tales of the Computer Age. New York: W.W. Norton, 1990. ISBN 978-0393307320. p.55. [return to text] Note 4: MIT Tech Talk was distributed all over the campus, and it was well worthwhile to pick it up and peruse the weekly calendar. It was possible for non-MIT readers to subscribe to receive it by mail (that is, by what is now called "snail-mail"). It was published in paper form through 2009, but is now available only on the web. [return to text] Note 5: In his talk, Shannon showed a way of profiting from random fluctuations in a stock's price, regardless of whether the overall trend was up or down. The method depended on being able to buy and sell quickly, without having to pay any commissions. If I recall, the upshot of all the math was that all you had to do was to keep a fixed amount of money invested in the stock. That meant that if the price dropped, you would buy some more, and if it rose, you would sell some. Intuitively, this means that you are buying low and selling high, and indeed, all the math showed this to be an optimal strategy. I don't know if the conclusion could have been of practical value to the brokerage firms. It was useless to me, because it assumed no commission charges. But a brokerage firm that was a member of the exchange might well be able to trade commission-free. [return to text] Note 6: Gabor's lecture that day was on a theoretical system that could be used to show three-dimensional movies without requiring the wearing by the viewers of any sort of glasses. But it required the use of a special spherical screen, with an emulsion that could develop reflective layers in depth, perpendicular to the plane of the emulsion. Although this could be done with a process developed by Gabriel Lippmann, the reflectivity of these emulsions at the time was not sufficient to create a workable screen, nor was it possible to fabricate a screen of movie-theater dimensions using Lippmann's technology. It seems that Gabor had a habit of proposing theoretical inventions that the technology of the time couldn't actually realize. [return to text] ![]() |