Work

Classification of Artin groups admitting retractions onto their parabolic subgroups

Year: 2026
Type: preprint
Abstract: We classify the Artin groups that admit retractions onto all of their parabolic subgroups. Our approach relies on a detailed analysis of triangular subgroups, with a key ingredient being the classification of homomorphisms between dihedral Artin groups that map one of the standard generators to a standard generator. As a consequence, we show that whenever an Artin group admits retractions to parabolic subgroups, it also admits ordinary ones - that is, retractions that send each standard generator either to a standard generator or to the identity.
Language: English
Open Access status: green
OpenAlex ID: W7138243716
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Cited by: 1
Related to: 10