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arXiv · 0801.3396

A local form for the automorphisms of the spectral unit ball

Pascal J. Thomas
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Abstract

If F is an automorphism of the spectral unit ball, we show that, in a neighborhood of any cyclic (i.e. non-derogatory) matrix of the ball, the map F can be written as conjugation by a holomorphically varying non singular matrix. This provides a shorter proof of a theorem of J. Rostand, with a slightly stronger result.

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Pascal J. Thomas. 2008-01-22. A local form for the automorphisms of the spectral unit ball. https://arxiv.org/abs/0801.3396

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