Discrete Duhamel product, restriction of weighted shift operators and related problems


KARAEV M. T. , SALTAN S. , KUNT T.

NEW YORK JOURNAL OF MATHEMATICS, cilt.20, ss.831-843, 2014 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 20
  • Basım Tarihi: 2014
  • Dergi Adı: NEW YORK JOURNAL OF MATHEMATICS
  • Sayfa Sayıları: ss.831-843

Özet

By applying the discrete Duhamel product method we calculate the spectral multiplicity of the direct sum of some operators. In particular, we prove that mu(T vertical bar X-i circle plus A) = 1 + mu(A) and mu(S circle plus A) = 2 for the restriction of the weighted shift operator T vertical bar X-i, shift operator S and some appropriate operators A on the Banach spaces.