"Quantitative measure of correlation," minipaper, 1955
Hugh Everett
Abstract
Before writing a first draft of the long thesis, Hugh Everett wrote three short papers, often refered to as his minipapers, for John Wheeler to review. This minipaper, called "Quantitative measure of correlation," lays some groundwork for the application of information theory as a measure of the degree of quantum correlation or entanglement. From very early in the project, Everett thought that Shannon information theory would provide insight into pure wave mechanics. While statistical measures, such as standard deviation, would have sufficed, Everett developed information-theoretic measures to represent such things as the width of distributions and the degree of correlation between the states of multiple systems. He thought that the standard quantum uncertainty relations were best expressed in an information theoretic way. The present document is the typed version of the minipaper that Wheeler would have seen and commented on.