2 papers
math-ph2022
On the Birman-Krein Theorem
Vanderléa R. Bazao, César R. de Oliveira, Pablo A. Diaz
It is shown that if is a unitary operator so that a singular subspace of~ is unitarily equivalent to a singular subspace of~ (or ), for each unitary operator~, th…
math-ph2007
Cantor Singular Continuous Spectrum for Operators Along Interval Exchange Transformations
M. Cobo, C. Gutierrez, C. R. de Oliveira
It is shown that Schroedinger operators, with potentials along the shift embedding of Lebesgue almost every interval exchange transformations, have Cantor spectrum of measure zero…