Irrational Exuberance (book) Irrational Exuberance (book) Irrational Exuberance is a March 2000 book written by American economist Robert J. Shiller, a Yale University professor and 2013 Nobel Prize winner. The book examines economic bubbles in the 1990s and early 2000s, and is named after Federal Reserve Chairman Alan Greenspan's famed "irrational exuberance" quote warning of such a possible bubble in 1996. Published at the height of the dot-com boom, the text put forth several arguments demonstrating how the stock markets were overvalued at the time. The stock market collapse of 2000 happened the exact month of the book's publication. The second edition of
Irrational rotation Irrational rotation In the mathematical theory of dynamical systems, an irrational rotation is a map where "θ" is an irrational number. Under the identification of a circle with R/Z, or with the interval [0, 1] with the boundary points glued together, this map becomes a rotation of a circle by a proportion "θ" of a full revolution (i.e., an angle of 2"πθ" radians). Since "θ" is irrational, the rotation has infinite order in the circle group and the map "T" has no periodic orbits. Alternatively, we can use multiplicative notation for an irrational rotation by introducing the map The relationship