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Division algebras of slice functions

Published online by Cambridge University Press:  15 March 2019

Riccardo Ghiloni
Affiliation:
Dipartimento di Matematica, Università di Trento, Via Sommarive 14, I-38123Povo, Italy (riccardo.ghiloni@unitn.it; alessandro.perotti@unitn.it)
Alessandro Perotti
Affiliation:
Dipartimento di Matematica, Università di Trento, Via Sommarive 14, I-38123Povo, Italy (riccardo.ghiloni@unitn.it; alessandro.perotti@unitn.it)
Caterina Stoppato
Affiliation:
Dipartimento di Matematica e Informatica ‘U. Dini’, Università di Firenze, Viale Morgagni 67/A, I-50134Firenze, Italy (stoppato@math.unifi.it)

Abstract

This work studies slice functions over finite-dimensional division algebras. Their zero sets are studied in detail along with their multiplicative inverses, for which some unexpected phenomena are discovered. The results are applied to prove some useful properties of the subclass of slice regular functions, previously known only over quaternions. Firstly, they are applied to derive from the maximum modulus principle a version of the minimum modulus principle, which is in turn applied to prove the open mapping theorem. Secondly, they are applied to prove, in the context of the classification of singularities, the counterpart of the Casorati-Weierstrass theorem.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 2019

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