RIP Paul Halmos (1916-2006)

On October 2nd, mathematician Paul Halmos died.

His book on finite vector fields (his first book, according to his wikipedia entry) was a supplementary text for a course I took at Tech. That's the first time I heard his name, which is among the most prominent of 20th century mathematicians. (I like synecdoches.) In his case, it's because of his exposition.

Halmos is apparently the first mathematician to use the "tombstone notation" to end a proof. Personally, I prefer QEFD.