Claude Shannon: Difference between revisions

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== Cryptography ==
== Cryptography ==


During World War II, Shannon performed classified research for the U. S. government on [[cryptography]]. His 1949 "Communication Theory of Secrecy Systems"<ref>{{cite paper
During World War II, Shannon performed classified research for the U. S. government on [[cryptography]]. His 1949 "Communication Theory of Secrecy Systems"<ref name=TheorySecrecy /> became the seminal paper for cryptography as an academic discipline.
| author = C. E. Shannon
| title = Communication Theory of Secrecy Systems
| journal = Bell Systems Technical Journal
| volume = 28
| date = 1949
| pages = pp.656-715
| url = http://netlab.cs.ucla.edu/wiki/files/shannon1949.pdf }}</ref> became the seminal paper for cryptography as an academic discipline.


== Publications ==
== Publications ==
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** ''This had important implications about the maximum amount of information that could be shoved into a given amount of spectrum before being overwhelmed by [[noise]], a fundamental limit that became known as [[Shannon's Law]].  It would be 45 years before the scientific world was able to verify all the predictions in this paper.''
** ''This had important implications about the maximum amount of information that could be shoved into a given amount of spectrum before being overwhelmed by [[noise]], a fundamental limit that became known as [[Shannon's Law]].  It would be 45 years before the scientific world was able to verify all the predictions in this paper.''
** ''This paper coined the use of the word "bit".''
** ''This paper coined the use of the word "bit".''
* '''Communication Theory of Secrecy Systems''', Bell System Technical Journal, vol. 28, pp. 656-715, 1949.
* '''Communication Theory of Secrecy Systems''', Bell System Technical Journal, vol. 28, pp. 656-715, 1949<ref name=TheorySecrecy />.
* '''Communication In The Presence Of Noise''', Proceedings of the Institute of Radio Engineers (IRE), vol. 37, pp. 10–21, Jan. 1949.<ref name-PresenceNoise>[https://dx.doi.org/10.1109/JRPROC.1949.232969 Communication In The Presence Of Noise] DOI 10.1109/JRPROC.1949.232969</ref>   
* '''Communication In The Presence Of Noise''', Proceedings of the Institute of Radio Engineers (IRE), vol. 37, pp. 10–21, Jan. 1949.<ref name-PresenceNoise>[https://dx.doi.org/10.1109/JRPROC.1949.232969 Communication In The Presence Of Noise] DOI 10.1109/JRPROC.1949.232969</ref>   
** ''This paper extends and elaborates on "A Mathematical Theory of Communication"''
** ''This paper extends and elaborates on "A Mathematical Theory of Communication"''
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<references>
<references>


<ref name=SymbolicAnalysis>[https://doi.org/10.1109/T-AIEE.1938.5057767 A symbolic analysis of relay and switching circuits] and freely downloadable at [https://dspace.mit.edu/handle/1721.1/11173;jsessionid=1749D77E60D489A8D9B511EE79B1DDDE MIT]; DOI 10.1109/T-AIEE.1938.5057767</ref>
<ref name=SymbolicAnalysis>
[https://doi.org/10.1109/T-AIEE.1938.5057767 A symbolic analysis of relay and switching circuits], downloadable at [https://dspace.mit.edu/handle/1721.1/11173;jsessionid=1749D77E60D489A8D9B511EE79B1DDDE MIT]; DOI 10.1109/T-AIEE.1938.5057767
</ref>
 
<ref name=TheorySecrecy>
[https://doi.org/10.1002/j.1538-7305.1949.tb00928.x Communication theory of secrecy systems], downloadable at [https://typeset.io/papers/communication-theory-of-secrecy-systems-2y1h3cz20a typeset.io]; DOI j.1538-7305.1949.tb00928.x
 
{{cite paper
| author = C. E. Shannon
| title = Communication Theory of Secrecy Systems
| journal = Bell Systems Technical Journal
| volume = 28
| date = 1949
| pages = pp.656-715
| url = http://netlab.cs.ucla.edu/wiki/files/shannon1949.pdf }}
</ref>


</references>
</references>

Revision as of 12:33, 4 January 2023

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Life-sized bust of Claude Shannon by sculptor Eugene Daub. At least six versions of this statue are on display at various institutions in the USA. Eugene Daub described Claude Shannon as "the most famous person most people have never heard of" and admitted that he was quite fond of this particular work.

Claude Shannon (1916-2001) was a theoretical mathematician and electrical engineer who is regarded as a key foundational researcher in computer and communications design. He has also frequently been referred to as "the father of information theory". Shannon studied at M.I.T., worked for a time at Bell Laboratories, and later returned to M.I.T. as a professor. Recognized as a premier voice in the engineering community from the 1940's onward, Shannon had become a figure of some public and popular acclaim by the time of his retirement. An enormous number of resources exist about him on the web, and also in the deep web (i.e., online resources which must be paid for). In his twilight years, Shannon suffered from Alzheimer's disease.

Switching algebra

Shannon made a critical step enabling hardware design of a computer in his 1938 MIT master's thesis, A symbolic analysis of relay and switching circuits[1], in which he associated boolean algebra, a kind of mathematical system that had been known for centuries, with the design of logic gates in digital hardware. Shannon called boolean algebra "switching algebra" in the context of digital hardware design.

Information Theory

The field of information theory was launched in 1948 by Shannon's ground-breaking, two-part paper "A Mathematical Theory of Communication" [2] It was shortly followed by a book [1] which has since been reprinted many times. Information theory is devoted to messages and signals using techniques drawn from mathematical probability, and linking discrete and continuous mathematics in ways that later turned out to be helpful, not just in the fields of communications and computers, but also on thinking about biological processes and linguistics. He was also a pioneer in developing methods for computers to play chess.

Cryptography

During World War II, Shannon performed classified research for the U. S. government on cryptography. His 1949 "Communication Theory of Secrecy Systems"[3] became the seminal paper for cryptography as an academic discipline.

Publications

This list is not complete, but it includes his most influential works. Papers are shown in order of appearance:

  • A symbolic analysis of relay and switching circuits, Thesis (M.S.), Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1937 (graduation finalized in 1940).[1]
    • This linked Boolean algebra to the design of digital circuits (and called it "Switching Algebra")
  • A Mathematical Theory of Cryptography, Memorandum MM 45-110-02, 1 Sept. 1945, Bell Laboratories. Classified at the time of its publication; now available through the British Library.
  • A Mathematical Theory of Communication, Bell System Technical Journal, published in two parts: July, vol. 27, pp. 379-423, and Oct., vol. 28, pp. 623-656, 1948.
    • This had important implications about the maximum amount of information that could be shoved into a given amount of spectrum before being overwhelmed by noise, a fundamental limit that became known as Shannon's Law. It would be 45 years before the scientific world was able to verify all the predictions in this paper.
    • This paper coined the use of the word "bit".
  • Communication Theory of Secrecy Systems, Bell System Technical Journal, vol. 28, pp. 656-715, 1949[3].
  • Communication In The Presence Of Noise, Proceedings of the Institute of Radio Engineers (IRE), vol. 37, pp. 10–21, Jan. 1949.Cite error: Invalid <ref> tag; invalid names, e.g. too many
    • This paper extends and elaborates on "A Mathematical Theory of Communication"
    • Reprinted in Proceedings of the IEEE, vol. 72, Issue 9, pp, 1192-1201, Sept. 1984.
    • Reprinted in Proceedings of the IEEE, vol. 86, Issue 2, pp. 447-457, Feb. 1998.
  • Probability of error for optimal codes in a Gaussian channel, Bell Systems Technical Journal, vol. 38, pp. 611–656, 1959.

Other statue instances

An instance of Eugene Daub's sculture stands at the entrance to Bell Laboratories (subsequently part of Alcatel-Lucent) in Murray Hill, NJ. Visitors regularly photograph it, often with themselves standing beside it. The photo shown here is within a 2013 Tweet by Mariette DiChristina.


References

  1. 1.0 1.1 A symbolic analysis of relay and switching circuits, downloadable at MIT; DOI 10.1109/T-AIEE.1938.5057767
  2. A Mathematical Theory of Communication by Claude Shannon, Bell System Technical Journal, July & October, 1948; now on ACM website, last access 10/10/2020
  3. 3.0 3.1 Communication theory of secrecy systems, downloadable at typeset.io; DOI j.1538-7305.1949.tb00928.x C. E. Shannon (1949). Communication Theory of Secrecy Systems.