On Nonnormal Matrices That Can Be Reduced to Band Form under Nite Sequences of Elementary Unitary Similarities
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چکیده
We say that a square complex matrix is condensable if it can be reduced to a bandform through a nite sequence of elementary uni-tary similarities. The two main results of this paper are the following assertions: (1) Any matrix with a low rank skew-Hermitian part is condens-able. (2) If A is a normal condensable matrix, then any rank one perturbation of A (generally nonnormal) is condensable as well.
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تاریخ انتشار 1996