Schrödinger Operators with Few Bound States
نویسندگان
چکیده
We show that whole-line Schrödinger operators with finitely many bound states have no embedded singular spectrum. In contradistinction, we show that embedded singular spectrum is possible even when the bound states approach the essential spectrum exponentially fast. We also prove the following result for oneand two-dimensional Schrödinger operators, H, with bounded positive ground states: Given a potential V , if both H ± V are bounded from below by the ground-state energy of H, then V ≡ 0.
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تاریخ انتشار 2005