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arXiv · 1601.06159

Some constants related to numerical ranges

Michel Crouzeix
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Abstract

In an attempt to progress towards proving the conjecture the numerical range W (A) is a 2--spectral set for the matrix A, we propose a study of various constants. We review some partial results, many problems are still open. We describe our corresponding numerical tests.

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Michel Crouzeix. 2016-01-22. Some constants related to numerical ranges. https://arxiv.org/abs/1601.06159

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