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On the connectivity of the hyperbolicity region of irreducible polynomials

Mario Denis Kummer
From the journal Advances in Geometry


We give a proof for the fact that an irreducible hyperbolic polynomial has only one pair of hyperbolicity cones. Apart from the use of Bertini’s Theorem the proof is elementary.

MSC 2010: 12D10; 14P10; 52A37

  1. Communicated by: C. Scheiderer


I would like to thank Daniel Plaumann, who encouraged me to write this note, and Eli Shamovich and Victor Vinnikov for some comments.


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Received: 2017-04-27
Published Online: 2018-01-24
Published in Print: 2019-04-24

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