[ m at h . SP ] 9 O ct 1 99 8 SPECTRAL INSTABILITY FOR SOME SCHRÖDINGER OPERATORS
نویسنده
چکیده
We define the concept of instability index of an isolated eigenvalue of a non-self-adjoint operator, and prove some of its general properties. We also describe a stable procedure for computing this index for Schrödinger operators in one dimension, and apply it to the complex resonances of a typical operator with a dilation analytic potential. AMS subject classification: 34L05, 35P05, 47A75, 49R99, 65L15
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