Optimal stopping is a math theory that can be used to solve real world decision problems. In the real world, it is often applied to help decide when to stop dating and get married.
Discovering Free Will (Part II, Part III) - a nice discussion of the Conway-Kochen "Free Will Theorem". [more inside]
Ronald Coase, the author of two of the most influential articles in economics died September 2 at the age of 102. In the 1961, in an article entitled "The Problem of Social Cost," he came up with the now famous "Coase Theorem" which is often used as the starting point of thinking about transaction costs and the necessity of certain rules and regulations when these costs are too high for individual agents to bear by themselves. Coase's work led to the development of various fields of research in economics and law. New Institutional economics (Oliver Williamson), Social Choice Theory (Duncan Black) and the Law and Economics movement in legal studies.
Futurama has always been a haven for geek humor, but last week's episode "The Prisoner of Benda" pushed things to the next level. First hinted at in an American Physical Society interview with showrunner David X. Cohen (previously), staff writer and mathematics Ph.D. Ken Keeler devised a novel mathematical proof based on group theory to resolve the logic puzzle spawned by the episode's brain-swapping (but no backsies!) conceit. Curious how it works? Read the proof (in the show or in plain text), then see it in action using this handy chart. Too much math for a lazy Sunday? Then entertain your brain with lengthy clips from the episode -- including two of the funniest moments in the series in the span of two minutes.
Did you know that you can create a simple set of directions to your house that works no matter where the recipient starts from? After 38 years this remarkable conjecture has now been proved by a 63-year old former security guard.
The Sarong Theorem Archive is the premier online repository for pictures of mathematicans in sarongs proving theorems.