Motion groupoids and mapping class groupoids

Autor: Torzewska, Fiona, Martins, João Faria, Martin, Paul Purdon

Publikováno v: Comm. Math. Phys. 402, 1621-1705 (2023)

Here $\underline{M}$ denotes a pair $(M,A)$ of a manifold and a subset (e.g. $A=\partial M$ or $A=\emptyset$). We construct for each $\underline{M}$ its motion groupoid $\mathrm{Mot}_{\underline{M}}$, whose object set is the power set $ {\mathcal P}

Externí odkaz: http://arxiv.org/abs/2103.10377

Almost-crystallographic groups as quotients of Artin braid groups

Autor: Oscar Ocampo, Daciberg Lima Gonçalves, John Guaschi

Publikováno v: Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual)
Universidade de São Paulo (USP)
instacron:USP
Journal of Algebra
Journal of Algebra, Elsevier, 2019, 524, pp.160-186. ⟨10.1016/j.jalgebra.2019.01.010⟩

Let n , k ≥ 3 . In this paper, we analyse the quotient group B n / Γ k ( P n ) of the Artin braid group B n by the subgroup Γ k ( P n ) belonging to the lower central series of the Artin pure braid group P n . We prove that it is an almost-crysta

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::569ab5769f4d1b614e400275dbeffea0