Stability of self-adjoint square roots and polar decompositions in inde®nite scalar product spaces
نویسندگان
چکیده
Continuity properties of factors in polar decompositions of matrices with respect to inde®nite scalar products are studied. The matrix having the polar decomposition and the inde®nite scalar product are allowed to vary. Closely related properties of a self-adjoint (with respect to an inde®nite scalar product) perturbed matrix to have a self-adjoint square root, or to have a representation of the form X X , are also studied. Ó 1999 Elsevier Science Inc. All rights reserved. AMS classi®cation: 15A63; 15A23
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