Leonhard Euler

Leonhard Euler was born in Basel in 1707 and trained under the Bernoullis at the University of Basel. He spent most of his career at the Imperial Russian Academy of Sciences in Saint Petersburg, with a long intermediate period at the Berlin Academy under Frederick the Great. He published more than 850 works — essays, monographs, and textbooks — across almost every branch of eighteenth-century mathematics and physics, including much that was simply unknown before him.

His contributions to classical mechanics begin with the 1736 textbook Mechanica, the first comprehensive treatment of Newtonian mechanics using the new calculus rather than the geometric methods of the Principia. He went on to derive the Euler–Lagrange equations of motion, the Euler equations of rigid-body dynamics (which govern every spinning top, planet, and gyroscope), the Euler equations of fluid flow, and the basic equations for the buckling of columns. The notation he introduced — f(x) for functions, e for the base of natural logarithms, i for the imaginary unit, π in its modern role, Σ for sums — is the notation still in use today.

He went blind in his right eye in 1738 and completely blind in 1771, but continued to produce mathematics at an astonishing rate through dictation. He died in Saint Petersburg in 1783, working until his last afternoon. His collected works, the Opera Omnia, run to over 70 volumes and are not yet complete.