Wild Spectral Behaviour of Anharmonic Oscillators
E. B. Davies · Bulletin of the London Mathematical Society · 2000
We show that the norms of the sequence of spectral projections of certain non-self-adjoint ordinary differential operators cannot be polynomially bounded. The proof involves the investigation of ‘tame’ bi-orthogonal systems in Banach spaces. 2000 Mathematics Subject Classification 34L10, 46B15.