Some results on the block numerical range

Document Type : Research Paper


1 University of Hormozgan

2 Vali-e-Asr University of Rafsanjan



The main results of this paper are generalizations of classical results from the numerical range to the block numerical range.
A different and simpler proof for the Perron-Frobenius theory on the block numerical range of an irreducible nonnegative matrix is given.
In addition, the Wielandt's lemma and the Ky Fan's theorem on the block numerical range are extended.


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