منابع مشابه
Some results on the polynomial numerical hulls of matrices
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In this paper, the behavior of the pseudopolynomial numerical hull of a square complex matrix with respect to structured perturbations and its radius is investigated.
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We extend the Wermer’s theorem, to describe the polynomial hull of compact sets lying on the boundary of a smooth strictly convex domain of Cn. We also extend the result to polynomial p-hulls and apply it to get properties of pluriharmonic or p.s.h. positive currents. RÉSUMÉ. Nous décrivons à la suite des travaux de Wermer, l’enveloppe polynomiale des ensembles compacts contenus dans le bord d’...
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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.
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We say that a subset of C n is hypoconvex if its complement is the union of complex hyperplanes. We say it is strictly hypoconvex if it is smoothly bounded hypoconvex and at every point of the boundary the real Hessian of its defining function is positive definite on the complex tangent space at that point. Let Bn be the open unit ball in C . Suppose K is a C compact manifold in ∂B1 × C , n > 1...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 1973
ISSN: 0022-1236
DOI: 10.1016/0022-1236(73)90063-3