par Szymański, Konrad;Weis, Stephan ;Życzkowski, Karol
Référence Linear algebra and its applications, 545, page (148-173)
Publication A Paraître, 2018-05
Référence Linear algebra and its applications, 545, page (148-173)
Publication A Paraître, 2018-05
Article révisé par les pairs
Résumé : | The joint numerical range W(F) of three hermitian 3-by-3 matrices F=(F1,F2,F3) is a convex and compact subset in R3. Generically we find that W(F) is a three-dimensional oval. Assuming dim(W(F))=3, every one- or two-dimensional face of W(F) is a segment or a filled ellipse. We prove that only ten configurations of these segments and ellipses are possible. We identify a triple F for each class and illustrate W(F) using random matrices and dual varieties. |