For every nonzero q with |q|<=1, the sharp spectral constant of the scaled q-numerical range is max{1, 2|q|/(1+sqrt(1-|q|^2))}.
Crouzeix’s Conjecture and Related Problems
2 Pith papers cite this work, alongside 15 external citations. Polarity classification is still indexing.
2
Pith papers citing it
15
external citations · Crossref
citation-role summary
background 1
citation-polarity summary
fields
math.FA 2roles
background 1polarities
background 1representative citing papers
For fixed diagonal and first superdiagonal determined by n points in the disk, the only contractive upper triangular matrix is the model matrix of the compressed shift.
citing papers explorer
-
Sharp spectral constants for scaled $q$-numerical ranges
For every nonzero q with |q|<=1, the sharp spectral constant of the scaled q-numerical range is max{1, 2|q|/(1+sqrt(1-|q|^2))}.
-
Contractive upper triangular matrices with prescribed diagonals and superdiagonals
For fixed diagonal and first superdiagonal determined by n points in the disk, the only contractive upper triangular matrix is the model matrix of the compressed shift.