Biographical Memoirs Volume 91 (2009) / Chapter Skim
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PETER ELIAS
PETER ELIAS
Pages 108-123
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From page 108... ...
Photograph courtesy MIT Museum.
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From page 109... ...
, predeceased him in 1993 after 43 years of marriage. Pete was distinguished not only for his research but also as the head of the Massachusetts Institute of Technology's Electrical Engineering Department during the crucial period from 1960 to 1966 when the department was changing its education from engineering practice to engineering science and when computer science was starting to be recognized as a major part of electrical engineering.
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From page 110... ...
He was fascinated by the intellectual beauty of Shannon's theory, and immediately realized, first, that it provided the right conceptual basis for communication engineering and, second, that a great deal of work remained to be done before the practical benefits of the theory could be realized. Norbert Wiener's contemporary work on cybernetics provided a complementary set of theories about communication, computation, and control.
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From page 111... ...
thesis, Pete was appointed as a junior fellow in the Harvard Society of Fellows and spent the next three years doing research on a variety of subjects, including writing several pioneering papers on optical communication, continuing his core research on information theory, and working with Noam Chomsky on syntactic characterization in linguistic theory.
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From page 112... ...
It was a more fundamental approach than his "Error-Free Coding," and it provided three giant steps toward the search for effective coding strategies. "Coding for Noisy Channels" is restricted to a particularly simple model of a noisy communication channel known as a binary symmetric channel, but this model contains all the significant conceptual problems of coding and decoding.
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From page 113... ...
Shannon showed that by making n very large and keeping the rate R = k/n in data bits per transmitted bit constant but less than capacity, the probability of correct decoding could be made to approach 0 with appropriately chosen coding and decoding. More surprisingly, Shannon proved his result by random choice of codewords, thus showing that the choice of code was not critical if the block length could be made arbitrarily large.
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From page 114... ...
The result was to change the focus in error-correction theory from finding the optimum block codes of given length to finding classes of codes with simple decoding algorithms. It is somewhat characteristic of Pete that this blockbuster paper appeared only in the convention record of a conference.
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From page 115... ...
Pete's contribution here was to show that if the channel bandwidth were some integer multiple of the source bandwidth and if feedback were available, then, using the appropriate simple strategy, the need for complex coding disappears. As with a number of Pete's results, it was a very special case that was analyzed, but the idea was applicable in much greater generality.
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From page 116... ...
Pete always had very broad interests, ranging across telecommunication, mathematics, the sciences, and liberal arts. He had also become a founding editor somewhat earlier of the journal Information and Control, which was intended to publish papers of somewhat broader scope than the Transactions on Information Theory.
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From page 117... ...
DEPARTMENT HEAD (1960-1966) In 1960 Pete was promoted to full professor and at the same time was appointed head of the Department of Electrical Engineering (later to become the Department of Electrical Engineering and Computer Science)
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From page 118... ...
The departmental politics, given the size of the department, were relatively benign, but the rapid changes on the horizon could have led to ugly repercussions without remarkable tact and understanding from the department head. Added to this, Pete was clearly an academic and an intellectual who fully enjoyed the pursuit of research problems.
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From page 119... ...
Before 1960 the department viewed its research mission as being divided between processing and transmitting information on one side and processing and transmitting energy on the other. By 1966 the information side had dwarfed the energy side, and the information side had split into a very large number of new areas, with computer science being the most rapidly growing.
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From page 120... ...
It is inappropriate to say he retired, since he still enjoyed coming to his office most days. He was still active advising students, organizing department colloquia, or simply playing an active role in the intellectual life of the community.
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From page 121... ...
1956 Coding for two noisy channels. In Information Theory: Third London Symposium, ed.
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From page 122... ...
IEEE Trans. Inform.
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