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Property C for ODE and applications

Alexander G. Ramm
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Abstract

An overview of the authors results is given. Property C for ODE is defioned, It is proved that the pair of Sturm-Liouville operators has property C. This property is applied to many inverse problems. Some well-known results, such as uniqueness of the recovery of the potential from scattering data, from the spectral function and from two spectra are proved in a new short way based on property C. Many new results are obtained. In particular, it is proved that a compactly supported potential can be uniquely recovered from the phase shift of s-wave alone, known at all energies, without knowledge of bound states and norming constants. The fixed-energy phase shifts known at some values of the angular momentum determine a compactly supported potential uniquely. Mixed data inverse problems are studied. Analysis of the Newton-Sabatier procedure is given. It is shown that this procedure is a parameter-fitting procedure rather than an inversion method. Other results on inverse problems are obtained.

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Alexander G. Ramm. 2000-11-17. Property C for ODE and applications. https://arxiv.org/abs/math-ph/0008002

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