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On the absolutely continuous spectrum of generalized indefinite strings II

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 نشر من قبل Jonathan Eckhardt
 تاريخ النشر 2019
  مجال البحث فيزياء
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We continue to investigate absolutely continuous spectrum of generalized indefinite strings. By following an approach of Deift and Killip, we establish stability of the absolutely continuous spectra of two more model examples of generalized indefinite strings under rather wide perturbations. In particular, one of these results allows us to prove that the absolutely continuous spectrum of the isospectral problem associated with the two-component Camassa-Holm system in a certain dispersive regime is essentially supported on the set $(-infty,-1/2]cup [1/2,infty)$.



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