# Online Encyclopedia

Categories: 1916 births | 2001 deaths | Computer pioneers | Cryptographers | Electrical engineers | Mathematicians

# Claude E. Shannon

**Claude Elwood Shannon** (April 30, 1916 - February 24, 2001) has been called "the father of information theory". Shannon was born in Petoskey, Michigan and was a distant relative of Thomas Edison. While growing up, he worked as a messenger for Western Union.

Shannon began studying electrical engineering and mathematics at the University of Michigan in 1932, and received his Bachelor's degree in 1936. He attended the Massachusetts Institute of Technology for graduate school, where he worked on Vannevar Bush's differential analyser, an analog computer.

He implemented Boolean algebra and binary arithmetic using electronic relays and switches for the first time in history in his 1937 MIT master's thesis, *A Symbolic Analysis of Relay and Switching Circuits* , and, with it, essentially founded practical digital circuit design. Professor Howard Gardner, of Harvard University, called Shannon's thesis "possibly the most important, and also the most famous, master's thesis of the century", and in 1940 it earned Shannon the Alfred Noble American Institute of American Engineers Award . After working at Cold Spring Harbor Laboratory, on genetics, Shannon worked on his Ph.D. in 1940 at MIT. His PhD Thesis is titled *An Algebra for Theoretical Genetics .* He then worked at Bell Labs until he returned to MIT in the 50s.

In 1948 Shannon published *A Mathematical Theory of Communication*. This work focuses on the problem of how to reconstruct at a target point the information a sender has transmitted. In this fundamental work he used tools in randomized analysis and large deviations , which were in their nascent development stages at that time. Shannon developed information entropy as a measure for redundancy while essentially inventing information theory. His later book with Warren Weaver, *The Mathematical Theory of Communication*, is brief and surprisingly accessible to the non-specialist. Another notable paper published in 1949 is *Communication Theory of Secrecy Systems*, a major contribution to the development of a mathematical theory of cryptography. He is also credited with the introduction of the Sampling Theory, which is concerned with representing a continuous-time signal from a (uniform) discrete set of samples.

Shannon is known for his thinking prowess; many have testified that he was able to write entire academic papers by dictating from memory alone, without correction. He was known to rarely scribble his thoughts on paper or blackboard, preferring to work everything out in his head. Outside of his academic pursuits, Shannon was interested in juggling, unicycling, and chess. He also invented many devices, including a chess-playing machine, a rocket-powered pogo stick, and a flame-throwing trumpet for a science exhibition. He met his wife Betty Shannon when she was a numerical analyst at Bell Labs.

From 1958 to 1978 he was a Professor at MIT. To commemorate his achievements, there were celebrations of his work in 2001, and there are currently 3 copies of a statue of Shannon: one at the University of Michigan, one at MIT and one at Bell Labs.

## See also

- Shannon-Hartley law
- Nyquist-Shannon sampling theorem
- Shannon capacity
- Shannon game
- Rate distortion theory
- Information theory
- Confusion and diffusion

## References

- C. E. Shannon:
*A mathematical theory of communication.*Bell System Technical Journal, vol. 27, pp. 379-423 and 623-656, July and October, 1948. - Claude E. Shannon and Warren Weaver:
*The Mathematical Theory of Communication.*The University of Illinois Press, Urbana, Illinois, 1949. ISBN 0252725484

## External links

- Summary of Shannons' life and career http://www.lucent.com/minds/infotheory/who.html
*Communication Theory of Secrecy Systems*http://www3.edgenet.net/dcowley/docs.html*A Mathematical Theory of Communication*http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html- Obituary at MIT http://web.mit.edu/newsoffice/nr/2001/shannon.html
- Retrospective at the University of Michigan http://www.engin.umich.edu/150th/alum-legends/shannon.html
- Notes on Computer-Generated Text http://www.nightgarden.com/infosci.htm

Categories: 1916 births | 2001 deaths | Computer pioneers | Cryptographers | Electrical engineers | Mathematicians