Quadratic Form Techniques and the Balslev-Combes Theorem
نویسندگان
چکیده
We extend the theorem of Balslev and Combes on the absence of singular continuous spectrum to a class of interactions including r~ (3/2 ̂ α < 2) local potentials. In addition, we note that the theory of sectorial operators allows a simplification of their proof and allows one to push the cuts through angles larger than the π/2 restriction employed by Balslev-Combes.
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