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On Unitary N-Dilations for Tuples of Circulant Contractions and von Neumann’s Inequality
Mathematics Department, Blessington Christian University, Nkayi, Republic of the Congo
Mathematics Department, Blessington Christian University, Nkayi, Republic of the Congo
Mathematics Department, N’Djamena University, N’Djamena, Tchad
- 1 Mathematics Department, Blessington Christian University, Nkayi, Republic of the Congo
- 2 Mathematics Department, Blessington Christian University, Nkayi, Republic of the Congo
- 3 Mathematics Department, N’Djamena University, N’Djamena, Tchad
American Journal of Computational Mathematics·Volume 13 (2023)·Pages 594–606·Published 13 October 2023·DOI10.4236/ajcm.2023.134032
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Abstract
We introduce the spectral mapping factorization of tuples of circulant matrices and its matrix version. We prove that every tuple of circulant contractions has a unitary N-dilation. We show that von Neumann’s inequality holds for tu ples of circulant contractions. We construct completely cont ract ive homomorphisms over the algebra of complex polynomials defined on .
KeywordsDilationsPolynomialsMatrices
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