Extensions of Jordan Bases for Invariant Subspaces of a Matrix
نویسندگان
چکیده
A characterization is obtained for the matrices A with the property that every (some) Jordan basis of every A-invariant subspace can be extended to a Jordan basis of A. These results are based on a criterion for a Jordan basis of an invariant subspace to be extendable to a Jordan basis of the whole space. The criterion involves two concepts: the constancy property and the depth property. "'Supported by Conselleria de Cultura Educacion y Ciencia de la Generalitat Valenciana. and by D .C.1. c.Y.T. of Ministerio de Educacion y Ciencia, Spain. tpartially supported by NSF grant DMS 88-02836. *Partially supported by NSF grants DMS 85-21521, DMS 89-01445, ECS 87-18971. LINEAR ALGEBRA AND ITS APPliCATIONS 150:209-225 (1991) 209 @ Elsevier Science Publishing Co., Inc., 1991 655 Avenue of the Americas, New York, NY 10010 0024-3795/91/$3.50 210 RAPHAEL BRU, LEIBA RODMAN, AND HANS SCHNEIDER
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