Chapman & Hall/CRC Applied Mathematics & Nonlinear Science

Unlike the classical Sturm theorems on the zeros of solutions of second-order ODEs, Sturm''s evolution zero set analysis for parabolic PDEs did not attract much attention in the 19th century, and, in fact, it was lost or forgotten for almost a century. Briefly revived by P,lya in the 1930''s and rediscovered in part several times since, it was not un