Ela Polynomial Numerical Hulls of Order
نویسنده
چکیده
In this note, analytic description of V 3 (A) is given for normal matrices of the form A = A 1 ⊕ iA 2 or A = A 1 ⊕ e i 2π 3 A 2 ⊕ e i 4π 3 A 3 , where A 1 , A 2 , A 3 are Hermitian matrices. The new concept " k th roots of a convex set " is used to study the polynomial numerical hulls of order k for normal matrices.
منابع مشابه
Some results on the polynomial numerical hulls of matrices
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 matriceswe show that $V^k(A)=sigma(A)$.
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