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20102026
most citedClassification of joint numerical ranges of three hermitian matrices of size three

40 citations · 250 across the 28 of their papers we have counts for

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math.FA2025

The joint numerical range of three hermitian matrices

Piotr Pikul, Ilya Spitkovsky, Konrad Szymański +2

We analyze the joint numerical range of three hermitian matrices of order four. In the generic case, this three-dimensional convex set has a smooth boundary. We analyze non-gen…

math.FA2025

Matrix systems, algebras, and open maps

Stephan Weis

Every state on the algebra of complex nxn matrices restricts to a state on any matrix system. Whereas the restriction to a matrix system is generally not open, we prove that…