Some results on the polynomial numerical hulls of matrices

Author(s):

H. R. Afshin , M. A. Mehrjoofard , A. Salemi

Abstract:
In this note we characterize polynomial numerical hulls of matrices $A in M_n$ such that $A^2$ is Hermitian. Also, we consider normal matrices $A in M_n$ whose $k^{th}$ power are semidefinite. For such matrices we show that $V^k(A)=sigma(A)$.
Keywords:

polynomial numerical hull , joint numerical range , normal matrices

Language:
English
Published:
Bulletin of Iranian Mathematical Society, Volume:39 Issue: 3, 2013
Pages:
569 to 578
https://www.magiran.com/p1150788