Eigenvalue avoidance

Prof Nick Trefethen ( Oxford University )

"Eigenvalue avoidance" or "level repulsion" refers to the tendency of eigenvalues of matrices or operators to be distinct rather than degenerate. The mathematics goes back to von Neumann and Wigner in 1929 and touches many subjects including numerical linear algebra, random matrix theory, chaotic dynamics, and number theory. This talk will be an informal illustrated discussion of various aspects of this phenomenon.