Edwin Jaynes

E. T. Jaynes
Edwin Thompson Jaynes (1922–1998), photo taken circa 1960.
Born	(1922-07-05)July 5, 1922 Waterloo, Iowa
Died	30 April 1998(1998-04-30) (aged 75) St. Louis, Missouri
Fields	Physicist
Institutions	Washington University
Alma mater	Princeton University
Thesis	An electronic theory of ferroelectricity (1948)
Doctoral advisor	Eugene Wigner
Doctoral students	G. Larry Bretthorst
Known for	MaxEnt interpretation, Bayesian theory

Edwin Thompson Jaynes (July 5, 1922 – April 30, 1998) was the Wayman Crow Distinguished Professor of Physics at Washington University in St. Louis. He wrote extensively on statistical mechanics and on foundations of probability and statistical inference, initiating in 1957 the MaxEnt interpretation of thermodynamics, as being a particular application of more general Bayesian/information theory techniques (although he argued this was already implicit in the works of Gibbs). Jaynes strongly promoted the interpretation of probability theory as an extension of logic.

In 1963, together with Fred Cummings, he modeled the evolution of a two-level atom in an electromagnetic field, in a fully quantized way. This model is known as the Jaynes–Cummings model.

A particular focus of his work was the construction of logical principles for assigning prior probability distributions; see the principle of maximum entropy, the principle of transformation groups and Laplace's principle of indifference. Other contributions include the mind projection fallacy.

Jaynes' posthumous book, Probability Theory: The Logic of Science (2003) gathers various threads of modern thinking about Bayesian probability and statistical inference, develops the notion of probability theory as extended logic, and contrasts the advantages of Bayesian techniques with the results of other approaches. This book was published posthumously in 2003 (from an incomplete manuscript that was edited by Larry Bretthorst). An unofficial list of errata is hosted by Kevin S. Van Horn.