Yearly Archives: 2011


John McCarthy, the mind behind Lisp, died yesterday at age 84. The photographs below are from one of his web sites at Stanford. Many of his papers are available through a different web page. (I don’t know how long either … Continue reading

Posted in computing | 5 Comments

The n-ball game

The area enclosed by a circle is πr2. The volume inside a sphere is 4∕3πr3. These are formulas I learned too early in life. Having committed them to memory as a schoolboy, I ceased to ask questions about their origin … Continue reading

Posted in featured, mathematics | 13 Comments

Divisive diversions

The ever-puzzling Peter Winkler offered three problems in the August Communications of the ACM: Does every positive integer divide some number of the form 1{0,1}*—that is, a positive integer whose decimal representation includes no digits other than 0 and 1? … Continue reading

Posted in computing, mathematics, problems and puzzles | 3 Comments

Driving the dreamboat

Slide behind the wheel of this dreamboat. Push the electronic control button. Then sit back and let transistors take over. There’s something curiously tentative about this vision of the future of motoring, as seen from 1964. You’re invited to push … Continue reading

Posted in computing, modern life | 6 Comments

Probabilities of probabilities

In simple games, one can calculate the exact probability of every outcome, and so the expected winnings can also be determined exactly…. When I wrote the words above in a recent American Scientist column, I didn’t think I was saying … Continue reading

Posted in mathematics, statistics | 6 Comments