Abstract
A time-variant analogue of an interpolation problem equivalent to the relaxed commutant lifting problem is introduced and studied. In a somewhat less general form the problem already appears in the analysis of the set of all solutions to the three chain completion problem. The interpolants are upper triangular operator matrices of which the columns induce contractive operators. The set of all solutions of the problem is described explicitly. The results presented are time-variant analogues of the main theorems in [23].
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Frazho, A.E., ter Horst, S., Kaashoek, M.A. (2009). A Time-variant Norm Constrained Interpolation Problem Arising from Relaxed Commutant Lifting. In: Grobler, J.J., Labuschagne, L.E., Möller, M. (eds) Operator Algebras, Operator Theory and Applications. Operator Theory: Advances and Applications, vol 195. Birkhäuser Basel. https://doi.org/10.1007/978-3-0346-0174-0_6
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