Henri Poincaré, a founding father of the modern theory of PDEs
By Brezis Haïm
I will discuss some contributions of Henri Poincaré which have had a major impact on the development of PDEs in the 20th century; in particular, the solution of the Laplace equation and some nonlinear problems associated with the Laplacian, the spectral theory of the Laplacian, and much more.