Claude Shannon

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory".[1][2] Shannon is noted for having founded information theory with a landmark paper, A Mathematical Theory of Communication, that he published in 1948.

He is also well known for founding digital circuit design theory in 1937, when—as a 21-year-old master's degree student at the Massachusetts Institute of Technology (MIT)—he wrote his thesis demonstrating that electrical applications of Boolean algebra could construct any logical numerical relationship.[3] Shannon contributed to the field of cryptanalysis for national defense during World War II, including his fundamental work on codebreaking and secure telecommunications.

Claude Shannon
ClaudeShannon MFO3807
BornApril 30, 1916
Petoskey, Michigan, United States
DiedFebruary 24, 2001 (aged 84)
Medford, Massachusetts, United States
Alma materUniversity of Michigan,
Known for
AwardsStuart Ballantine Medal (1955)
IEEE Medal of Honor (1966)
National Medal of Science (1966)
Harvey Prize (1972)
Claude E. Shannon Award (1972)
Harold Pender Award (1978)
John Fritz Medal (1983)
Kyoto Prize (1985)
National Inventors Hall of Fame (2004)
Scientific career
FieldsMathematics and electronic engineering
InstitutionsBell Labs
Institute for Advanced Study
Doctoral advisorFrank Lauren Hitchcock
Doctoral studentsDanny Hillis
Ivan Sutherland
Bert Sutherland



Shannon was born in Petoskey, Michigan and grew up in Gaylord, Michigan.[4] His father, Claude, Sr. (1862–1934), a descendant of early settlers of New Jersey, was a self-made businessman, and for a while, a Judge of Probate. Shannon's mother, Mabel Wolf Shannon (1890–1945), was a language teacher, and also served as the principal of Gaylord High School.

Most of the first 16 years of Shannon's life were spent in Gaylord, where he attended public school, graduating from Gaylord High School in 1932. Shannon showed an inclination towards mechanical and electrical things. His best subjects were science and mathematics. At home he constructed such devices as models of planes, a radio-controlled model boat and a barbed-wire telegraph system to a friend's house a half-mile away.[5] While growing up, he also worked as a messenger for the Western Union company.

His childhood hero was Thomas Edison, who he later learned was a distant cousin. Both Shannon and Edison were descendants of John Ogden (1609–1682), a colonial leader and an ancestor of many distinguished people.[6][7]

Shannon was apolitical and an atheist.[8]

Logic circuits

In 1932, Shannon entered the University of Michigan, where he was introduced to the work of George Boole. He graduated in 1936 with two bachelor's degrees: one in electrical engineering and the other in mathematics.

In 1936, Shannon began his graduate studies in electrical engineering at MIT, where he worked on Vannevar Bush's differential analyzer, an early analog computer.[9] While studying the complicated ad hoc circuits of this analyzer, Shannon designed switching circuits based on Boole's concepts. In 1937, he wrote his master's degree thesis, A Symbolic Analysis of Relay and Switching Circuits.[10] A paper from this thesis was published in 1938.[11] In this work, Shannon proved that his switching circuits could be used to simplify the arrangement of the electromechanical relays that were used then in telephone call routing switches. Next, he expanded this concept, proving that these circuits could solve all problems that Boolean algebra could solve. In the last chapter, he presented diagrams of several circuits, including a 4-bit full adder.[10]

Using this property of electrical switches to implement logic is the fundamental concept that underlies all electronic digital computers. Shannon's work became the foundation of digital circuit design, as it became widely known in the electrical engineering community during and after World War II. The theoretical rigor of Shannon's work superseded the ad hoc methods that had prevailed previously. Howard Gardner called Shannon's thesis "possibly the most important, and also the most noted, master's thesis of the century."[12]

Shannon received his Ph.D. degree from MIT in 1940. Vannevar Bush had suggested that Shannon should work on his dissertation at the Cold Spring Harbor Laboratory, in order to develop a mathematical formulation for Mendelian genetics. This research resulted in Shannon's PhD thesis, called An Algebra for Theoretical Genetics.[13]

In 1940, Shannon became a National Research Fellow at the Institute for Advanced Study in Princeton, New Jersey. In Princeton, Shannon had the opportunity to discuss his ideas with influential scientists and mathematicians such as Hermann Weyl and John von Neumann, and he also had occasional encounters with Albert Einstein and Kurt Gödel. Shannon worked freely across disciplines, and this ability may have contributed to his later development of mathematical information theory.[14]

Wartime research

Shannon then joined Bell Labs to work on fire-control systems and cryptography during World War II, under a contract with section D-2 (Control Systems section) of the National Defense Research Committee (NDRC).

Shannon is credited with the invention of signal-flow graphs, in 1942. He discovered the topological gain formula while investigating the functional operation of an analog computer.[15]

For two months early in 1943, Shannon came into contact with the leading British mathematician Alan Turing. Turing had been posted to Washington to share with the U.S. Navy's cryptanalytic service the methods used by the British Government Code and Cypher School at Bletchley Park to break the ciphers used by the Kriegsmarine U-boats in the north Atlantic Ocean.[16] He was also interested in the encipherment of speech and to this end spent time at Bell Labs. Shannon and Turing met at teatime in the cafeteria.[16] Turing showed Shannon his 1936 paper that defined what is now known as the "Universal Turing machine";[17][18] This impressed Shannon, as many of its ideas complemented his own.

In 1945, as the war was coming to an end, the NDRC was issuing a summary of technical reports as a last step prior to its eventual closing down. Inside the volume on fire control, a special essay titled Data Smoothing and Prediction in Fire-Control Systems, coauthored by Shannon, Ralph Beebe Blackman, and Hendrik Wade Bode, formally treated the problem of smoothing the data in fire-control by analogy with "the problem of separating a signal from interfering noise in communications systems."[19] In other words, it modeled the problem in terms of data and signal processing and thus heralded the coming of the Information Age.

Shannon's work on cryptography was even more closely related to his later publications on communication theory.[20] At the close of the war, he prepared a classified memorandum for Bell Telephone Labs entitled "A Mathematical Theory of Cryptography," dated September 1945. A declassified version of this paper was published in 1949 as "Communication Theory of Secrecy Systems" in the Bell System Technical Journal. This paper incorporated many of the concepts and mathematical formulations that also appeared in his A Mathematical Theory of Communication. Shannon said that his wartime insights into communication theory and cryptography developed simultaneously and that "they were so close together you couldn’t separate them".[21] In a footnote near the beginning of the classified report, Shannon announced his intention to "develop these results … in a forthcoming memorandum on the transmission of information."[22]

While he was at Bell Labs, Shannon proved that the cryptographic one-time pad is unbreakable in his classified research that was later published in October 1949. He also proved that any unbreakable system must have essentially the same characteristics as the one-time pad: the key must be truly random, as large as the plaintext, never reused in whole or part, and be kept secret.[23]

Information theory

In 1948, the promised memorandum appeared as "A Mathematical Theory of Communication," an article in two parts in the July and October issues of the Bell System Technical Journal. This work focuses on the problem of how best to encode the information a sender wants to transmit. In this fundamental work, he used tools in probability theory, developed by Norbert Wiener, which were in their nascent stages of being applied to communication theory at that time. Shannon developed information entropy as a measure of the uncertainty in a message while essentially inventing the field of information theory. In 1949 Claude Shannon and Robert Fano devised a systematic way to assign code words based on probabilities of blocks.[24] This technique, known as Shannon-Fano coding, was first proposed in the 1948 article.

The book, co-authored with Warren Weaver, The Mathematical Theory of Communication, reprints Shannon's 1948 article and Weaver's popularization of it, which is accessible to the non-specialist. Warren Weaver pointed out that the word "information" in communication theory is not related to what you do say, but to what you could say. That is, information is a measure of one's freedom of choice when one selects a message. Shannon's concepts were also popularized, subject to his own proofreading, in John Robinson Pierce's Symbols, Signals, and Noise.

Information theory's fundamental contribution to natural language processing and computational linguistics was further established in 1951, in his article "Prediction and Entropy of Printed English", showing upper and lower bounds of entropy on the statistics of English – giving a statistical foundation to language analysis. In addition, he proved that treating whitespace as the 27th letter of the alphabet actually lowers uncertainty in written language, providing a clear quantifiable link between cultural practice and probabilistic cognition.

Another notable paper published in 1949 is "Communication Theory of Secrecy Systems", a declassified version of his wartime work on the mathematical theory of cryptography, in which he proved that all theoretically unbreakable ciphers must have the same requirements as the one-time pad. He is also credited with the introduction of sampling theory, which is concerned with representing a continuous-time signal from a (uniform) discrete set of samples. This theory was essential in enabling telecommunications to move from analog to digital transmissions systems in the 1960s and later.

He returned to MIT to hold an endowed chair in 1956.

Teaching at MIT

In 1956 Shannon joined the MIT faculty to work in the Research Laboratory of Electronics (RLE). He continued to serve on the MIT faculty until 1978.

Later life

Shannon developed Alzheimer's disease and spent the last few years of his life in a nursing home in Massachusetts oblivious to the marvels of the digital revolution he had helped create. He died in 2001. He was survived by his wife, Mary Elizabeth Moore Shannon, his son, Andrew Moore Shannon, his daughter, Margarita Shannon, his sister, Catherine Shannon Kay, and his two granddaughters.[25][26] His wife stated in his obituary that, had it not been for Alzheimer's disease, "He would have been bemused" by it all.[27]

Hobbies and inventions

Minivac 601
The Minivac 601, a digital computer trainer designed by Shannon.

Outside of Shannon's academic pursuits, he was interested in juggling, unicycling, and chess. He also invented many devices, including a Roman numeral computer called THROBAC, juggling machines, and a flame-throwing trumpet.[28] One of his more humorous devices was a box kept on his desk called the "Ultimate Machine", based on an idea by Marvin Minsky. Otherwise featureless, the box possessed a single switch on its side. When the switch was flipped, the lid of the box opened and a mechanical hand reached out, flipped off the switch, then retracted back inside the box. In addition, he built a device that could solve the Rubik's Cube puzzle.[6]

Shannon designed the Minivac 601, a digital computer trainer to teach business people about how computers functioned. It was sold by the Scientific Development Corp starting in 1961.

He is also considered the co-inventor of the first wearable computer along with Edward O. Thorp.[29] The device was used to improve the odds when playing roulette.

Personal life

Shannon married Norma Levor, a wealthy, Jewish, left-wing intellectual in January 1940. The marriage ended in divorce after about a year. Levor later married Ben Barzman.[30]

Shannon met his second wife Betty Shannon (née Mary Elizabeth Moore) when she was a numerical analyst at Bell Labs. They were married in 1949.[25] Betty assisted Claude in building some of his most famous inventions.[31]

Claude and Betty Shannon had three children, Robert James Shannon, Andrew Moore Shannon, and Margarita Shannon, and raised his family in Winchester, Massachusetts. Their oldest son, Robert Shannon, died in 1998 at the age of 45.

After suffering from a progressive decline over some years due to Alzheimer's disease, Shannon died at the age of 85, on February 24, 2001.[32]


To commemorate Shannon's achievements, there were celebrations of his work in 2001.

There are currently six statues of Shannon sculpted by Eugene Daub: one at the University of Michigan; one at MIT in the Laboratory for Information and Decision Systems; one in Gaylord, Michigan; one at the University of California, San Diego; one at Bell Labs; and another at AT&T Shannon Labs.[33] After the breakup of the Bell System, the part of Bell Labs that remained with AT&T Corporation was named Shannon Labs in his honor.

According to Neil Sloane, an AT&T Fellow who co-edited Shannon's large collection of papers in 1993, the perspective introduced by Shannon's communication theory (now called information theory) is the foundation of the digital revolution, and every device containing a microprocessor or microcontroller is a conceptual descendant of Shannon's publication in 1948:[34] "He's one of the great men of the century. Without him, none of the things we know today would exist. The whole digital revolution started with him."[27] The unit shannon is named after Claude Shannon.

A Mind at Play, a biography of Shannon written by Jimmy Soni and Rob Goodman, was published in 2017.[35]

On April 30, 2016 Shannon was honored with a Google Doodle to celebrate his life on what would have been his 100th birthday.[36][37][38][39][40][41]

Other work

Shannon and his electromechanical mouse Theseus (named after Theseus from Greek mythology) which he tried to have solve the maze in one of the first experiments in artificial intelligence.

Shannon's mouse

"Theseus", created in 1950, was a magnetic mouse controlled by an electromechanical relay circuit that enabled it to move around a labyrinth of 25 squares. Its dimensions were the same as those of an average mouse.[2] The maze configuration was flexible and it could be modified arbitrarily by rearranging movable partitions.[2] The mouse was designed to search through the corridors until it found the target. Having travelled through the maze, the mouse could then be placed anywhere it had been before, and because of its prior experience it could go directly to the target. If placed in unfamiliar territory, it was programmed to search until it reached a known location and then it would proceed to the target, adding the new knowledge to its memory and learning new behavior.[2] Shannon's mouse appears to have been the first artificial learning device of its kind.[2]

Shannon's estimate for the complexity of chess

In 1949 Shannon completed a paper (published in March 1950) which estimates the game-tree complexity of chess, which is approximately 10120. This number is now often referred to as the "Shannon number", and is still regarded today as an accurate estimate of the game's complexity. The number is often cited as one of the barriers to solving the game of chess using an exhaustive analysis (i.e. brute force analysis).[42][43]

Shannon's computer chess program

On March 9, 1949, Shannon presented a paper called "Programming a Computer for playing Chess." The paper was presented at the National Institute for Radio Engineers Convention in New York. He described how to program a computer to play chess based on position scoring and move selection. He proposed basic strategies for restricting the number of possibilities to be considered in a game of chess. In March 1950 it was published in Philosophical Magazine, and is considered one of the first articles published on the topic of programming a computer for playing chess, and using a computer to solve the game.[42][44] His process for having the computer decide on which move to make was a minimax procedure, based on an evaluation function of a given chess position. Shannon gave a rough example of an evaluation function in which the value of the black position was subtracted from that of the white position. Material was counted according to the usual chess piece relative value (1 point for a pawn, 3 points for a knight or bishop, 5 points for a rook, and 9 points for a queen).[45] He considered some positional factors, subtracting ½ point for each doubled pawn, backward pawn, and isolated pawn. Another positional factor in the evaluation function was mobility, adding 0.1 point for each legal move available. Finally, he considered checkmate to be the capture of the king, and gave the king the artificial value of 200 points. Quoting from the paper:

The coefficients .5 and .1 are merely the writer's rough estimate. Furthermore, there are many other terms that should be included. The formula is given only for illustrative purposes. Checkmate has been artificially included here by giving the king the large value 200 (anything greater than the maximum of all other terms would do).

The evaluation function was clearly for illustrative purposes, as Shannon stated. For example, according to the function, pawns that are doubled as well as isolated would have no value at all, which is clearly unrealistic.

Shannon's maxim

Shannon formulated a version of Kerckhoffs' principle as "The enemy knows the system". In this form it is known as "Shannon's maxim".


Shannon Centenary

Claude Shannon Centenary Logo
Claude Shannon Centenary

The Shannon Centenary, 2016, marked the life and influence of Claude Elwood Shannon on the hundredth anniversary of his birth on April 30, 1916. It was inspired in part by the Alan Turing Year. An ad hoc committee of the IEEE Information Theory Society including Christina Fragouli, Rüdiger Urbanke, Michelle Effros, Lav Varshney and Sergio Verdú,[46] coordinated worldwide events. The initiative was announced in the History Panel at the 2015 IEEE Information Theory Workshop Jerusalem[47][48] and the IEEE Information Theory Society Newsletter.[49]

A detailed listing of confirmed events was available on the website of the IEEE Information Theory Society.[50]

Some of the planned activities included:

  • Bell Labs hosted the First Shannon Conference on the Future of the Information Age on April 28 – 29, 2016 in Murray Hill, NJ to celebrate Claude Shannon and the continued impact of his legacy on society. The event includes keynote speeches by global luminaries and visionaries of the information age who will explore the impact of information theory on society and our digital future, informal recollections, and leading technical presentations on subsequent related work in other areas such as bioinformatics, economic systems, and social networks. There is also a student competition
  • Bell Labs launched a Web exhibit on April 30, 2016, chronicling Shannon's hiring at Bell Labs (under an NDRC contract with US Government), his subsequent work there from 1942 through 1957, and details of Mathematics Department. The exhibit also displayed bios of colleagues and managers during his tenure, as well as original versions of some of the technical memoranda which subsequently became well known in published form.
  • The Republic of Macedonia is planning a commemorative stamp. A USPS commemorative stamp is being proposed, with an active petition.[51]
  • A documentary on Claude Shannon and on the impact of information theory, The Bit Player, is being produced by Sergio Verdú and Mark Levinson.
  • A trans-Atlantic celebration of both George Boole's bicentenary and Claude Shannon's centenary that is being led by University College Cork and the Massachusetts Institute of Technology. A first event was a workshop in Cork, When Boole Meets Shannon,[52] and will continue with exhibits at the Boston Museum of Science and at the MIT Museum.[53]
  • Many organizations around the world are holding observance events, including the Boston Museum of Science, the Heinz-Nixdorf Museum, the Institute for Advanced Study, Technische Universität Berlin, University of South Australia (UniSA), Unicamp (Universidade Estadual de Campinas), University of Toronto, Chinese University of Hong Kong, Cairo University, Telecom ParisTech, National Technical University of Athens, Indian Institute of Science, Indian Institute of Technology Bombay, Indian Institute of Technology Kanpur, Nanyang Technological University of Singapore, University of Maryland, University of Illinois at Chicago, École Polytechnique Federale de Lausanne, The Pennsylvania State University (Penn State), University of California Los Angeles, Massachusetts Institute of Technology, Chongqing University of Posts and Telecommunications, and University of Illinois at Urbana-Champaign.
  • A series of geocaches, dedicated to the work of Claude Shannon, will be deployed in Munich, Germany. The first cache has already been placed.[54]
  • A logo that appears on this page was crowdsourced on Crowdspring.[55]
  • The Math Encounters presentation of May 4, 2016 at the National Museum of Mathematics in New York, titled Saving Face: Information Tricks for Love and Life, focused on Shannon's work in Information Theory. A video recording and other material are available.[56]

Awards and honors list

The Claude E. Shannon Award was established in his honor; he was also its first recipient, in 1972.[57]

See also


  1. ^ James, I. (2009). "Claude Elwood Shannon 30 April 1916 – 24 February 2001". Biographical Memoirs of Fellows of the Royal Society. 55: 257–265. doi:10.1098/rsbm.2009.0015.
  2. ^ a b c d e "Bell Labs Advances Intelligent Networks". Archived from the original on July 22, 2012.
  3. ^ Poundstone, William (2005). Fortune's Formula : The Untold Story of the Scientific Betting System That Beat the Casinos and Wall Street. Hill & Wang. ISBN 978-0-8090-4599-0.
  4. ^ "Claude Shannon". Retrieved September 10, 2014.
  5. ^ "The Lives They Lived: Claude Shannon", New York Times, 30 December 2001
  6. ^ a b MIT Professor Claude Shannon dies; was founder of digital communications, MIT — News office, Cambridge, Massachusetts, February 27, 2001
  7. ^ Sloane, N.J.A; Wyner, Aaron D., eds. (1993). Claude Elwood Shannon: Collected Papers. Wiley/IEEE Press. ISBN 978-0-7803-0434-5. Retrieved 9 December 2016.
  8. ^ William Poundstone (2010). Fortune's Formula: The Untold Story of the Scientific Betting System. Macmillan. p. 18. ISBN 978-0-374-70708-8. Shannon described himself as an atheist and was outwardly apolitical.
  9. ^ Robert Price (1982). "Claude E. Shannon, an oral history". IEEE Global History Network. IEEE. Retrieved July 14, 2011.
  10. ^ a b Claude Shannon, "A Symbolic Analysis of Relay and Switching Circuits," unpublished MS Thesis, Massachusetts Institute of Technology, August 10, 1937.
  11. ^ Shannon, C. E. (1938). "A Symbolic Analysis of Relay and Switching Circuits". Trans. AIEE. 57 (12): 713–723. doi:10.1109/T-AIEE.1938.5057767. hdl:1721.1/11173.
  12. ^ Gardner, Howard (1987). The Mind's New Science: A History of the Cognitive Revolution. Basic Books. p. 144. ISBN 0-465-04635-5.
  13. ^ C. E. Shannon, "An algebra for theoretical genetics," (Ph.D. Thesis, Massachusetts Institute of Technology, 1940), MIT-THESES//1940–3 Online text at MIT — Contains a biography on pp. 64–65.
  14. ^ Erico Marui Guizzo, “The Essential Message: Claude Shannon and the Making of Information Theory” (M.S. Thesis, Massachusetts Institute of Technology, Dept. of Humanities, Program in Writing and Humanistic Studies, 2003), 14.
  15. ^ Okrent, Howard; McNamee, Lawrence P. (1970). "3. 3 Flowgraph Theory". NASAP-70 User's and Programmer's manual (PDF). Los Angeles, California: School of Engineering and Applied Science, University of California at Los Angeles. pp. 3–9. Retrieved 2016-03-04.
  16. ^ a b Hodges, Andrew (1992), Alan Turing: The Enigma, London: Vintage, pp. 243–252, ISBN 978-0-09-911641-7
  17. ^ Turing, A.M. (1936), "On Computable Numbers, with an Application to the Entscheidungsproblem", Proceedings of the London Mathematical Society, 2 (published 1937), 42, pp. 230–65, doi:10.1112/plms/s2-42.1.230
  18. ^ Turing, A.M. (1938), "On Computable Numbers, with an Application to the Entscheidungsproblem: A correction", Proceedings of the London Mathematical Society, 2 (published 1937), 43 (6), pp. 544–6, doi:10.1112/plms/s2-43.6.544
  19. ^ David A. Mindell, Between Human and Machine: Feedback, Control, and Computing Before Cybernetics, (Baltimore: Johns Hopkins University Press), 2004, pp. 319-320. ISBN 0-8018-8057-2.
  20. ^ David Kahn, The Codebreakers, rev. ed., (New York: Simon and Schuster), 1996, pp. 743–751. ISBN 0-684-83130-9.
  21. ^ quoted in Kahn, The Codebreakers, p. 744.
  22. ^ quoted in Erico Marui Guizzo, "The Essential Message: Claude Shannon and the Making of Information Theory," Archived May 28, 2008, at the Wayback Machine unpublished MS thesis, Massachusetts Institute of Technology, 2003, p. 21.
  23. ^ Shannon, Claude (1949). "Communication Theory of Secrecy Systems". Bell System Technical Journal 28 (4): 656–715.
  24. ^ Wolfram, Stephen (2002). A New Kind of Science. Wolfram Media, Inc. p. 1069. ISBN 1-57955-008-8.
  25. ^ a b Weisstein, Eric. "Shannon, Claude Elwood (1916–2001)". World of Scientific Biography. Wolfram Research.
  26. ^ "Claude Shannon – computer science theory". The History of Computing Project. Retrieved 9 December 2016.
  27. ^ a b Bell Labs digital guru dead at 84 — Pioneer scientist led high-tech revolution (The Star-Ledger, obituary by Kevin Coughlin February 27, 2001)
  28. ^ "People: Shannon, Claude Elwood". MIT Museum. Retrieved 9 December 2016.
  29. ^ The Invention of the First Wearable Computer Online paper by Edward O. Thorp of Edward O. Thorp & Associates
  30. ^ Jimmy Soni; Rob Goodman (2017). A Mind At Play: How Claude Shannon Invented the Information Age. Simon and Schuster. pp. 63, 80.
  31. ^ "Betty Shannon, Unsung Mathematical Genius". Scientific American Blog Network. Retrieved 2017-07-26.
  32. ^ Johnson, George. "Claude Shannon, Mathematician, Dies at 84". Retrieved 2018-10-04.
  33. ^ "Claude Shannon Statue Dedications". Archived from the original on July 31, 2010.
  34. ^ C. E. Shannon: A mathematical theory of communication. Bell System Technical Journal, vol. 27, pp. 379–423 and 623–656, July and October 1948
  35. ^ George Dyson (21 July 2017). "The Elegance of Ones and Zeroes". Wall Street Journal. Retrieved 15 August 2017.
  36. ^ Claude Shannon’s 100th birthday Google, 2016
  37. ^ Katie Reilly (April 30, 2016). "Google Doodle Honors Mathematician-Juggler Claude Shannon". Time.
  38. ^ Menchie Mendoza (2 May 2016). "Google Doodle Celebrates 100th Birthday Of Claude Shannon, Father Of Information Theory". Tech Times.
  39. ^ "Google Doodle commemorates 'father of information theory' Claude Shannon on his 100th birthday". Firstpost. May 3, 2016.
  40. ^ Jonathan Gibbs (29 April 2016). "Claude Shannon: Three things you'll wish you owned that the mathematician invented". The Independent.
  41. ^ David Z. Morris (April 30, 2016). "Google Celebrates 100th Birthday of Claude Shannon, the Inventor of the Bit". Fortune.
  42. ^ a b Claude Shannon (1950). "Programming a Computer for Playing Chess" (PDF). Philosophical Magazine. 41 (314).
  43. ^ Dr. James Grime. "How many chess games are possible? (films by Brady Haran). MSRI, Mathematical Sciences". Numberphile, July 24, 2015.
  44. ^
  45. ^ Hamid Reza Ekbia (2008), Artificial dreams: the quest for non-biological intelligence, Cambridge University Press, p. 46, ISBN 978-0-521-87867-8
  46. ^ "Newsletter". IEEE Information Theory Society. IEEE. June 2015.
  47. ^ "Videos". Israel: Technion.
  48. ^ "Sergio Verdú". Twitter.
  49. ^ "Newsletter". IEEE Information Theory Society. IEEE. September 2014.
  50. ^ "Shannon Centenary". IEEE Information Theory Society. IEEE.
  51. ^ "Shannon's centenary US postal stamp".
  52. ^ "-George Boole 200-Conferences". Archived from the original on September 6, 2015. Retrieved September 21, 2015.
  53. ^ "Compute and Communicate – A Boole/Shannon Celebration".
  54. ^ Geocaching. "GC6ACQE Shanniversary #1: Information Theory (DE/EN) (Traditional Cache) in Bayern, Germany created by sigurd_fjoelskaldr".
  55. ^ "crowdSPRING".
  56. ^ "Saving Face: Information Tricks for Love and Life (Math Encounters Presentation at the National Museum of Mathematics". ).
  57. ^ Roberts, Siobhan (30 April 2016). "Claude Shannon, the Father of the Information Age, Turns 1100100". The New Yorker. Retrieved 30 April 2016.
  58. ^ "IEEE Morris N. Liebmann Memorial Award Recipients" (PDF). IEEE. Archived from the original (PDF) on 2016-03-03. Retrieved February 27, 2011.
  59. ^ "IEEE Medal of Honor Recipients" (PDF). IEEE. Archived from the original (PDF) on 2015-04-22. Retrieved February 27, 2011.
  60. ^ "C.E. Shannon (1916–2001)". Royal Netherlands Academy of Arts and Sciences. Retrieved 17 July 2015.
  61. ^ "Award Winners (chronological)". Eduard Rhein Foundation. Archived from the original on July 18, 2011. Retrieved February 20, 2011.

Further reading

  • Claude E. Shannon: A Mathematical Theory of Communication, Bell System Technical Journal, Vol. 27, pp. 379–423, 623–656, 1948. [1]
  • Claude E. Shannon and Warren Weaver: The Mathematical Theory of Communication. The University of Illinois Press, Urbana, Illinois, 1949. ISBN 0-252-72548-4
  • Rethnakaran Pulikkoonattu — Eric W. Weisstein: Mathworld biography of Shannon, Claude Elwood (1916–2001) [2]
  • Claude E. Shannon: Programming a Computer for Playing Chess, Philosophical Magazine, Ser.7, Vol. 41, No. 314, March 1950. (Available online under External links below)
  • David Levy: Computer Gamesmanship: Elements of Intelligent Game Design, Simon & Schuster, 1983. ISBN 0-671-49532-1
  • Mindell, David A., "Automation's Finest Hour: Bell Labs and Automatic Control in World War II", IEEE Control Systems, December 1995, pp. 72–80.
  • David Mindell, Jérôme Segal, Slava Gerovitch, "From Communications Engineering to Communications Science: Cybernetics and Information Theory in the United States, France, and the Soviet Union" in Walker, Mark (Ed.), Science and Ideology: A Comparative History, Routledge, London, 2003, pp. 66–95.
  • Poundstone, William, Fortune's Formula, Hill & Wang, 2005, ISBN 978-0-8090-4599-0
  • Gleick, James, The Information: A History, A Theory, A Flood, Pantheon, 2011, ISBN 978-0-375-42372-7
  • Jimmy Soni and Rob Goodman, A Mind at Play: How Claude Shannon Invented the Information Age, Simon and Schuster, 2017, ISBN 978-1476766683
  • Nahin, Paul J., The Logician and the Engineer: How George Boole and Claude Shannon Create the Information Age, Princeton University Press, 2013, ISBN 978-0691151007
  • Everett M. Rogers, Claude Shannon's Cryptography Research During World War II and the Mathematical Theory of Communication, 1994 Proceedings of IEEE International Carnahan Conference on Security Technology, pp. 1-5, 1994. [3]

External links

A Mathematical Theory of Communication

"A Mathematical Theory of Communication" is an article by mathematician Claude E. Shannon published in Bell System Technical Journal in 1948. It was renamed The Mathematical Theory of Communication in the book of the same name, a small but significant title change after realizing the generality of this work.

A Symbolic Analysis of Relay and Switching Circuits

A Symbolic Analysis of Relay and Switching Circuits is the title of a master's thesis written by computer science pioneer Claude E. Shannon while attending the Massachusetts Institute of Technology (MIT) in 1937. In his thesis, Shannon, a dual degree graduate of the University of Michigan, proved that Boolean algebra could be used to simplify the arrangement of the relays that were the building blocks of the electromechanical automatic telephone exchanges of the day. Shannon went on to prove that it should also be possible to use arrangements of relays to solve Boolean algebra problems.

The utilization of the binary properties of electrical switches to perform logic functions is the basic concept that underlies all electronic digital computer designs. Shannon's thesis became the foundation of practical digital circuit design when it became widely known among the electrical engineering community during and after World War II. At the time, the methods employed to design logic circuits were ad hoc in nature and lacked the theoretical discipline that Shannon's paper supplied to later projects.

Psychologist Howard Gardner described Shannon's thesis as "possibly the most important, and also the most famous, master's thesis of the century". A version of the paper was published in the 1938 issue of the Transactions of the American Institute of Electrical Engineers, and in 1940, it earned Shannon the Alfred Noble American Institute of American Engineers Award.

Biographical Memoirs of Fellows of the Royal Society

The Biographical Memoirs of Fellows of the Royal Society is an academic journal on the history of science published annually by the Royal Society. It publishes obituaries of Fellows of the Royal Society. It was established in 1932 as Obituary Notices of Fellows of the Royal Society and obtained its current title in 1955, with volume numbering restarting at 1. Prior to 1932, obituaries were published in the Proceedings of the Royal Society.

The memoirs are a significant historical record and most include a full bibliography of works by the subjects. The memoirs are often written by a scientist of the next generation, often one of the subject's own former students, or a close colleague. In many cases the author is also a Fellow. Notable biographies published in this journal include Albert Einstein, Alan Turing, Bertrand Russell, Claude Shannon, Clement Attlee, Ernst Mayr, and Erwin Schrödinger.Each year around 20 to 25 memoirs of deceased Fellows of the Royal Society are collated by the Editor-in-Chief, currently Malcolm Longair, who succeeded Trevor Stuart in 2016. All content more than one year old is freely available to read.


The bit is a basic unit of information in information theory, computing, and digital communications. The name is a portmanteau of binary digit.In information theory, one bit is typically defined as the information entropy of a binary random variable that is 0 or 1 with equal probability, or the information that is gained when the value of such a variable becomes known. As a unit of information, the bit has also been called a shannon, named after Claude Shannon.

As a binary digit, the bit represents a logical value, having only one of two values. It may be physically implemented with a two-state device. These state values are most commonly represented as either 0or1, but other representations such as true/false, yes/no, +/−, or on/off are possible. The correspondence between these values and the physical states of the underlying storage or device is a matter of convention, and different assignments may be used even within the same device or program.

The symbol for the binary digit is either simply bit per recommendation by the IEC 80000-13:2008 standard, or the lowercase character b, as recommended by the IEEE 1541-2002 and IEEE Std 260.1-2004 standards. A group of eight binary digits is commonly called one byte, but historically the size of the byte is not strictly defined.

Communication Theory of Secrecy Systems

"Communication Theory of Secrecy Systems" is a paper published in 1949 by Claude Shannon discussing cryptography from the viewpoint of information theory. It is one of the foundational treatments (arguably the foundational treatment) of modern cryptography. It is also a proof that all theoretically unbreakable ciphers must have the same requirements as the one-time pad.

Shannon published an earlier version of this research in the classified report A Mathematical Theory of Cryptography, Memorandum MM 45-110-02, Sept. 1, 1945, Bell Laboratories. This classified report also precedes the publication of his "A Mathematical Theory of Communication", which appeared in 1948.

Confusion and diffusion

In cryptography, confusion and diffusion are two properties of the operation of a secure cipher identified by Claude Shannon in his 1945 classified report A Mathematical Theory of Cryptography. These properties, when present, work to thwart the application of statistics and other methods of cryptanalysis.

These concepts are also important in the design of robust hash functions and pseudorandom number generators where decorrelation of the generated values is of paramount importance.

David Slepian

David S. Slepian (June 30, 1923 – November 29, 2007) was an American mathematician. He is best known for his work with algebraic coding theory, probability theory, and distributed source coding. He was colleagues with Claude Shannon and Richard Hamming at Bell Labs.

Edward O. Thorp

Edward Oakley Thorp (born August 14, 1932) is an American mathematics professor, author, hedge fund manager, and blackjack player. He pioneered the modern applications of probability theory, including the harnessing of very small correlations for reliable financial gain.Thorp is the author of Beat the Dealer, which mathematically proved that the house advantage in blackjack could be overcome by card counting. He also developed and applied effective hedge fund techniques in the financial markets, and collaborated with Claude Shannon in creating the first wearable computer.Thorp received his Ph.D. in mathematics from the University of California, Los Angeles in 1958, and worked at the Massachusetts Institute of Technology (MIT) from 1959 to 1961. He was a professor of mathematics from 1961 to 1965 at New Mexico State University, and then joined the University of California, Irvine where he was a professor of mathematics from 1965 to 1977 and a professor of mathematics and finance from 1977 to 1982.

Gibbs algorithm

In statistical mechanics, the Gibbs algorithm, introduced by J. Willard Gibbs in 1902, is a criterion for choosing a probability distribution for the statistical ensemble of microstates of a thermodynamic system by minimizing the average log probability

subject to the probability distribution pi satisfying a set of constraints (usually expectation values) corresponding to the known macroscopic quantities. in 1948, Claude Shannon interpreted the negative of this quantity, which he called information entropy, as a measure of the uncertainty in a probability distribution. In 1957, E.T. Jaynes realized that this quantity could be interpreted as missing information about anything, and generalized the Gibbs algorithm to non-equilibrium systems with the principle of maximum entropy and maximum entropy thermodynamics.

Physicists call the result of applying the Gibbs algorithm the Gibbs distribution for the given constraints, most notably Gibbs's grand canonical ensemble for open systems when the average energy and the average number of particles are given. (See also partition function).

This general result of the Gibbs algorithm is then a maximum entropy probability distribution. Statisticians identify such distributions as belonging to exponential families.

Innovation (signal processing)

In time series analysis (or forecasting) — as conducted in statistics, signal processing, and many other fields — the innovation is the difference between the observed value of a variable at time t and the optimal forecast of that value based on information available prior to time t. If the forecasting method is working correctly, successive innovations are uncorrelated with each other, i.e., constitute a white noise time series. Thus it can be said that the innovation time series is obtained from the measurement time series by a process of 'whitening', or removing the predictable component. The use of the term innovation in the sense described here is due to Hendrik Bode and Claude Shannon (1950) in their discussion of the Wiener filter problem, although the notion was already implicit in the work of Kolmogorov.

List of game theorists

This is a list of notable economists, mathematicians, political scientists, and computer scientists whose work has added substantially to the field of game theory. For a list of people in the field of video games rather than game theory, please see list of ludologists.

Derek Abbott - quantum game theory and Parrondo's games

Susanne Albers - algorithmic game theory and algorithm analysis

Kenneth Arrow - voting theory (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 1972)

Robert Aumann - equilibrium theory (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 2005)

Robert Axelrod - repeated Prisoner's Dilemma

Tamer Başar - dynamic game theory and application robust control of systems with uncertainty

Cristina Bicchieri - epistemology of game theory

Olga Bondareva - Bondareva–Shapley theorem

Steven Brams - cake cutting, fair division, theory of moves

Jennifer Tour Chayes - algorithmic game theory and auction algorithms

John Horton Conway - combinatorial game theory

William Hamilton - evolutionary biology

John Harsanyi - equilibrium theory (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 1994)

Monika Henzinger - algorithmic game theory and information retrieval

Naira Hovakimyan - differential games and adaptive control

Peter L. Hurd - evolution of aggressive behavior

Rufus Isaacs - differential games

Anna Karlin - algorithmic game theory and online algorithms

Michael Kearns - algorithmic game theory and computational social science

Sarit Kraus - non-monotonic reasoning

John Maynard Smith - evolutionary biology

Oskar Morgenstern - social organization

John Forbes Nash - Nash equilibrium (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 1994)

John von Neumann - Minimax theorem, expected utility, social organization, arms race

J. M. R. Parrondo - games with a reversal of fortune, such as Parrondo's games

Charles E. M. Pearce - games applied to queuing theory

George R. Price - theoretical and evolutionary biology

Anatol Rapoport - Mathematical psychologist, early proponent of tit-for-tat in repeated Prisoner's Dilemma

Julia Robinson - proved that fictitious play dynamics converges to the mixed strategy Nash equilibrium in two-player zero-sum games

Alvin E. Roth - market design (Nobel Memorial Prize in Economic Sciences 2012)

Ariel Rubinstein - bargaining theory, learning and language

Thomas Jerome Schaefer - computational complexity of perfect-information games

Suzanne Scotchmer - patent law incentive models

Reinhard Selten - bounded rationality (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 1994)

Claude Shannon - studied cryptography and chess; sometimes called "the father of information theory"

Lloyd Shapley - Shapley value and core concept in coalition games (Nobel Memorial Prize in Economic Sciences 2012)

Thomas Schelling - bargaining (Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel 2005) and models of segregation

Myrna Wooders - coalition theory

Nyquist–Shannon sampling theorem

In the field of digital signal processing, the sampling theorem is a fundamental bridge between continuous-time signals (often called "analog signals") and discrete-time signals (often called "digital signals"). It establishes a sufficient condition for a sample rate that permits a discrete sequence of samples to capture all the information from a continuous-time signal of finite bandwidth.

Strictly speaking, the theorem only applies to a class of mathematical functions having a Fourier transform that is zero outside of a finite region of frequencies. Intuitively we expect that when one reduces a continuous function to a discrete sequence and interpolates back to a continuous function, the fidelity of the result depends on the density (or sample rate) of the original samples. The sampling theorem introduces the concept of a sample rate that is sufficient for perfect fidelity for the class of functions that are bandlimited to a given bandwidth, such that no actual information is lost in the sampling process. It expresses the sufficient sample rate in terms of the bandwidth for the class of functions. The theorem also leads to a formula for perfectly reconstructing the original continuous-time function from the samples.

Perfect reconstruction may still be possible when the sample-rate criterion is not satisfied, provided other constraints on the signal are known. (See § Sampling of non-baseband signals below and compressed sensing.) In some cases (when the sample-rate criterion is not satisfied), utilizing additional constraints allows for approximate reconstructions. The fidelity of these reconstructions can be verified and quantified utilizing Bochner's theorem.The name Nyquist–Shannon sampling theorem honors Harry Nyquist and Claude Shannon. The theorem was also discovered independently by E. T. Whittaker, by Vladimir Kotelnikov, and by others. It is thus also known by the names Nyquist–Shannon–Kotelnikov, Whittaker–Shannon–Kotelnikov, Whittaker–Nyquist–Kotelnikov–Shannon, and cardinal theorem of interpolation.

Product cipher

In cryptography, a product cipher combines two or more transformations in a manner intending that the resulting cipher is more secure than the individual components to make it resistant to cryptanalysis. The product cipher combines a sequence of simple transformations such as substitution (S-box), permutation (P-box), and modular arithmetic. The concept of product ciphers is due to Claude Shannon, who presented the idea in his foundational paper, Communication Theory of Secrecy Systems.

For transformation involving reasonable number of n message symbols, both of the foregoing cipher systems (the S-box and P-box) are by themselves wanting. Shannon suggested using a combination of S-box and P-box transformation—a product cipher. The combination could yield a cipher system more powerful than either one alone. This approach of alternatively applying substitution and permutation transformation has been used by IBM in the Lucifer cipher system, and has become the standard for national data encryption standards such as the Data Encryption Standard and the Advanced Encryption Standard. A product cipher that uses only substitutions and permutations is called a SP-network. Feistel ciphers are an important class of product ciphers.

Shannon (unit)

The shannon (symbol: Sh), more commonly known as the bit, is a unit of information and of entropy defined by IEC 80000-13. One shannon is the information content of an event occurring when its probability is ​1⁄2. It is also the entropy of a system with two equally probable states. If a message is made of a sequence of a given number of bits, with all possible bit strings being equally likely, the message's information content expressed in shannons is equal to the number of bits in the sequence. For this and historical reasons, the shannon is more commonly known as the bit. The introduction of the term shannon provides an explicit distinction between the amount of information that is expressed and the quantity of data that may be used to represent the information. IEEE Std 260.1-2004 still defines the unit for this meaning as the bit, with no mention of the shannon.

The shannon can be converted to other information units according to

The shannon is named after Claude Shannon, the founder of information theory.

Shannon coding

In the field of data compression, Shannon coding, named after its creator, Claude Shannon, is a lossless data compression technique for constructing a prefix code based on a set of symbols and their probabilities (estimated or measured). It is suboptimal in the sense that it does not achieve the lowest possible expected code word length like Huffman coding does, and never better but sometimes equal to the Shannon-Fano coding.

The method was the first of its type, the technique was used to prove Shannon's noiseless coding theorem in his 1948 article "A Mathematical Theory of Communication", and is therefore a centerpiece of the information age.

This coding method gave rise to the field of information theory and without its contribution, the world would not have any of the many successors; for example Shannon-Fano coding, Huffman coding, or arithmetic coding. Much of our day-to-day lives are significantly influenced by digital data and this would not be possible without Shannon coding and its ongoing evolution of its predecessor coding methods.

In Shannon coding, the symbols are arranged in order from most probable to least probable, and assigned codewords by taking the first bits from the binary expansions of the cumulative probabilities Here denotes the ceiling function (which rounds up to the next integer value).

Shannon number

The Shannon number, named after Claude Shannon, is a conservative lower bound (not an estimate) of the game-tree complexity of chess of 10120, based on an average of about 103 possibilities for a pair of moves consisting of a move for White followed by one for Black, and a typical game lasting about 40 such pairs of moves.

Shannon switching game

The Shannon switching game is an abstract strategy game for two players, invented by American mathematician and electrical engineer Claude Shannon, the "father of information theory" some time before 1951. Two players take turns coloring the edges of an arbitrary graph. One player has the goal of connecting two distinguished vertices by a path of edges of their color. The other player aims to prevent this by using their color instead (or, equivalently, by erasing edges). The game is commonly played on a rectangular grid; this special case of the game was independently invented by American mathematician David Gale in the late 1950s and is known as Gale or Bridg-It.

Shannon–Fano coding

In the field of data compression, Shannon–Fano coding, named after Claude Shannon and Robert Fano, is a technique for constructing a prefix code based on a set of symbols and their probabilities (estimated or measured). It is suboptimal in the sense that it does not achieve the lowest possible expected code word length like Huffman coding.The technique was proposed in Shannon's "A Mathematical Theory of Communication", his 1948 article introducing the field of information theory. The method was attributed to Fano, who later published it as a technical report.

Shannon–Fano coding should not be confused with Shannon coding, the coding method used to prove Shannon's noiseless coding theorem, or with Shannon–Fano–Elias coding (also known as Elias coding), the precursor to arithmetic coding.

Shannon–Hartley theorem

In information theory, the Shannon–Hartley theorem tells the maximum rate at which information can be transmitted over a communications channel of a specified bandwidth in the presence of noise. It is an application of the noisy-channel coding theorem to the archetypal case of a continuous-time analog communications channel subject to Gaussian noise. The theorem establishes Shannon's channel capacity for such a communication link, a bound on the maximum amount of error-free information per time unit that can be transmitted with a specified bandwidth in the presence of the noise interference, assuming that the signal power is bounded, and that the Gaussian noise process is characterized by a known power or power spectral density. The law is named after Claude Shannon and Ralph Hartley.

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