| Abstrakt: |
In this note it is proved that if W(z) are J-contractive matrix-functions which are meromorphic in the disk ¦z¦<1 (J−W(z)JW(z)≥0, J=J, J=I), W(z)→W(z) as n→∞, and then there exists a subsequence $$W_{n_k }$$ (z) whose boundary values It follows from this result that every convergent Blaschke-Potapov product has J-unitary boundary values. 1. Let J be a fixed self-adjoint unitary matrix, i.e., J = J and J = I. A matrix W is called J-contractive (J-unitary) if J−W JW⩾0 ( J−W JW=0). [ABSTRACT FROM AUTHOR] |
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