KTH/SU Mathematics Colloquium

05-02-23

Jan-Erik Björk, SU

Fundamental solution to PDE's and the Weyl algebra

The aim of this talk is to show that interplay between analysis and algebra often is very fruitful. To construct a tempered fundamental solution to a differential operator P(D) with constant coefficients means , via the Fourier transform, that the polynomial P(z) is inverted in the space S'(R^n) of tempered distributions. To find such an inverse one uses algebraic results about the Weyl Algebra A_n which is the non-commutative algebra of differential operators with polynomial coefficients. Some results due to Sato and Bernstein will be exposed together with some specific examples such as the construction of fundamental solutions to PDE's of real principal type with an optimal small analytic wave front set.