Template:Selected anniversaries/December 23
1722: Mathematician and academic Pierre Varignon dies. He simplified the proofs of many propositions in mechanics, adapted Leibniz's calculus to the inertial mechanics of Newton's Principia, and treated mechanics in terms of the composition of forces.
1822: Inventor and engineer Wilhelm Bauer born. He will design and invent submarines.
1933: Mathematician Rikitarō Fujisawa dies. During the Meiji era he was instrumental in reforming mathematics education in Japan and establishing the ideas of European mathematics in Japan.
1948: Mathematician Wilhelm Ackermann publishes his research on applications of the Ackermann function to detecting and preventing crimes against mathematical constants.
2016: Signed first edition of Blue City Sunset purchased for an undisclosed amount by "a well-known Gnomon algorithm theorist residing in New Minneapolis, Canada."