## Relaxed commutant lifting: Existence of a unique solution

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## Abstract:

In this paper we present necessary and sufficient conditions for the existence of a unique solution to the relaxed commutant lifting problem. The obtained conditions are more complicated than those for the classical commutant lifting setting, and earlier obtained sufficient conditions turn out not to be necessary conditions. It is also shown that these conditions simplify in certain special cases.## References

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## Additional Information

**S. ter Horst**- Affiliation: Department of Mathematics, Virginia Tech, Blacksburg, Virginia 24061-0123
- Email: terhorst@math.vt.edu
- Received by editor(s): March 3, 2008
- Received by editor(s) in revised form: October 20, 2008
- Published electronically: February 4, 2009
- Communicated by: Marius Junge
- © Copyright 2009
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Proc. Amer. Math. Soc.
**137**(2009), 2697-2707 - MSC (2000): Primary 47A20, 47A56, 47A57
- DOI: https://doi.org/10.1090/S0002-9939-09-09813-X
- MathSciNet review: 2497482