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Letters to the Editor Letters to the Editor Nathan Rosen and Black Judaism. Merzbacher has informed There is another advantage of tablet Mountain me that Professor Rosen used to apps which, being unfamiliar with Thank you for your excellent article return to Chapel Hill during the sum- them, the author doesn’t anticipate: in the February 2013 Notices on von mers where he collaborated with Merz- no matter how many blackboards Neumann and the book review of bacher on various research projects. are available, total space is limited, Transcending Tradition. Having been but the apps can store an unlimited educated in North Carolina, I was —Paul F. Zweifel number of handwritten screens. If an especially interested in the discus- Virginia Tech (emeritus) audience member wants a copy of the sion of Black Mountain College in [email protected] notes after a talk, I can either print a the latter. One prominent faculty copy or email the stored document. member there not mentioned in the (Received January 22, 2013) The apps can even record audio from review was the Jewish physicist (and In Defense of Technology for the presentation. disciple of Einstein) Nathan Rosen. Mathematical Talks I think what the author observes about use of computer-based slides Although I earned my Ph.D. in phys- In response to V. V. Peller’s com- today represents not a failure of the ics at Duke University, I was allowed mentary, “Utilization of technology computer as a platform for the pre- to take courses at the University of for mathematical talks: An alarming sentation, but rather inadequately North Carolina in Chapel Hill. I took situation” [Notices, February 2013]: creative use of the platform for a advantage of this leniency to take I sympathize with many of the dynamic presentation. All I ask is that three courses from Professor Rosen author’s points, but disagree with the author not blame the computer who had left Black Mountain to join the tendency to blame the computer for presentations by people who the U.N.C. faculty. This was a real as a platform for mathematical pre- don’t know how to take advantage of thrill for me, as Professor Rosen was sentations, and by extension the famous for his studies of the hydro- such a powerful tool. conclusion that conferences should gen molecule and, more so, for his be required to provide blackboards —Tom Leathrum discovery, along with Boris Podolsky for presenters. I, too, dislike heavy Jacksonville State University and Einstein, of the so-called “EPR reliance on slides, especially when [email protected] Paradox” of quantum mechanics, a cluttered with dense notation. For subject of much theoretical debate short presentations, I use slides my- (Received January 25, 2013) and experimental study throughout self, but few of them, typically fewer the twentieth century. (It was the than ten for a fifteen- to twenty- Displaced Mathematicians: A inspiration for the seminal work in- minute talk. Slides should provide Plea for Accuracy volving Bell’s Theorem, for example.) only some linear structure, not much I was a little bit puzzled by the front Rosen was more or less forced to content, for a talk. I frequently switch cover of the February 2013 Notices leave U.N.C. by the threat of a U.S. between slides and other software to (Vol. 60, No. 3). Who is counted as government investigation of his al- show graphics or interactive demon- “displaced”? For example, Heinz leged “communist sympathies”. (The strations. Hopf moved to Zurich in 1931 as university was by no means complicit The same has been true since be- the successor of Hermann Weyl, in his departure.) He and his wife fore computers became a mainstream who then took up a chair in Göt- emigrated to Israel where he lived mode for presentations: when giv- tingen (see, e.g., http://www-gap. to a ripe old age and did very well, ing a short talk using an overhead dcs.st-and.ac.uk/history/ becoming, as I recall, president of the projector, I would always have a Biographies/Hopf.html). Weyl Ben-Gurion University. I had the op- few prepared slides, and carry blank thereafter left Göttingen in 1933 be- portunity to visit him twice in Israel slides and dry-erase pens so that I cause of the Nazis. So Hopf was not and once he visited me in Ann Arbor, could be prepared to take a different “displaced”, but left Germany when where I was teaching at the time. He path based on audience response. In he accepted a regular job offer (he always greeted me as an old friend. a longer talk or class, I frequently use stayed in Switzerland until his death; If I am not mistaken, the vacancy a computer, but almost never slides: in 1943 he took Swiss citizenship created by Rosen’s departure was I use a tablet computer with an app because the Nazi authorities caused filled by a close friend of mine, Eugen such as LectureNotes (by Acadoid, trouble). But I might consider Weyl as Merzbacher, who went on to become for Android) or Notability (by Ginger “displaced”, even though he moved chairman of the U.N.C. physics de- Labs, for iOS), which turns the tablet out of Germany of his free will, before partment, president of the Ameri- into a portable whiteboard when con- he was forced out. can Physical Society, and author of nected to a projector. a definitive textbook on quantum The author acknowledges both the —Peter J. Huber mechanics. He is still in Chapel Hill, advantage of computers for present- Altendorf, Switzerland living with his wife now in a retire- ing difficult graphics and the problem [email protected] ment home and still active, although of having to turn lights on and off and well into his nineties, in various put screens up and down when using (Received February 7, 2013) activities related to physics and both a blackboard and a computer. MAY 2013 NOTICES OF THE AMS 543.
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