Mathematician, philosopher, soldier, scientist—René Descartes was the definition of a Renaissance man.

PHYSICS
He helped develop atomic bombs, but wanted nuclear science to be used for peace.
Before the 20th century, concert musicians might tune their instruments to wildly different pitches, depending on where they were playing.
Scientists have found a hack to help you quell the sound until the plumber comes.
The current record may never be broken.
Mental Floss spoke to ETH Zurich archivist Michael Gasser about the papers—including one letter in which Einstein calls his good friend a "frozen whale."
Fluid dynamics has never tasted so good.
We turned to mathematicians, physicists, and engineers to find out why the lights are so frustrating—and how to improve them.
Conservators used light imaging techniques to spot a tiny windmill sketch that's invisible to the naked eye.