Alfonso Castro
Harvey Mudd College
This will be introductory presentation of results and techniques on the solvability of equations of the form L(u) + N(u) =0
where L is a linear operator with discrete spectrum. The role of the interaction of the spectrum of N'(u) with respect to the spectrum of L will be emphasized. Basic examples are given when L is the Laplacian operator, D’Alembert’s operator, and integral operators.
![](https://ci6.googleusercontent.com/proxy/RnNZfQn2o2xpggJQqefCOervMbPIci5mujDPJnvl43kv6Rtxjyh5gHN_JKVzeU-aaGz3pePFgxfoAAtZJZNx8mveVTc-11j98EfuAJVcumUenA=s0-d-e1-ft#https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif)