Time is scarce, and lately I’ve been devoting it mostly to things other than blogging — but I feel the need to emerge from hiding just long enough to acknowledge the shocking death today of the extraordinary mathematician Vladimir Voevodsky at the age of 51.

Voevodsky is best known for finding the right definition of motivic cohomology sometime around the year 2000. This was a Holy Grail, the quest for which had been set in motion by the earth-shattering vision of Alexander Grothendieck. I happen to have been leafing through my well-worn copy of Voevodsky’s book on Cycles, Transfers and Motivic Homology Theories (co-written with Andrei Suslin and Eric Friedlander) when I heard of his death.

More recently, Voevodsky had turned his attention to logic and the foundations of mathematics. Here is video of his talk “What if the Current Foundations of Mathematics Are Inconsistent?”

A brief obituary is here. A brief mathematical autobiography, written by Voevodsky, is here. I might return and add a few personal reminscences.