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A Generalization to Ordered Groups of a Kreĭn Theorem

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Recent Advances in Matrix and Operator Theory

Part of the book series: Operator Theory: Advances and Applications ((OT,volume 179))

Abstract

We give an extension result for positive definite operator-valued Toeplitz-Krein-Cotlar triplets defined on an interval of an ordered group. When the triplet is positive definite and measurable we give a representation result.

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References

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Author information

Authors and Affiliations

  1. Escuela de Matemática, Fac. Ciencias Universidad Central de Venezuela, Apartado Postal 47686, Caracas, 1041-A, Venezuela

    Ramón Bruzual

  2. Escuela de Matemática, Fac. Ciencias Universidad Central de Venezuela, Apartado Postal 47159, Caracas, 1041-A, Venezuela

    Marisela Domínguez

Authors
  1. Ramón Bruzual
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  2. Marisela Domínguez
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Editor information

Editors and Affiliations

  1. Department of Mathematics, Virginia Tech, Blacksburg, VA, 24061, USA

    Joseph A. Ball

  2. School of Mathematical Sciences Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, 69978, Israel

    Yuli Eidelman

  3. Department of Mathematics, University of California San Diego, 9500 Gilman Drive, La Jolla, California, 92093-0112, USA

    J. William Helton

  4. Department of Mathematics, University of Connecticut, 196 Auditorium Road, U-9, Storrs, CT, 06269, USA

    Vadim Olshevsky

  5. Department of Mathematics, University of Virginia, P. O. Box 400137, Charlottesville, VA, 22904-4137, USA

    James Rovnyak

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© 2007 Birkhäuser Verlag Basel/Switzerland

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Bruzual, R., Domínguez, M. (2007). A Generalization to Ordered Groups of a Kreĭn Theorem. In: Ball, J.A., Eidelman, Y., Helton, J.W., Olshevsky, V., Rovnyak, J. (eds) Recent Advances in Matrix and Operator Theory. Operator Theory: Advances and Applications, vol 179. Birkhäuser Basel. https://doi.org/10.1007/978-3-7643-8539-2_6

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