A structure theorem for 2-hypergroupoids with topological applications
ISSN: 0010-0757
Año de publicación: 1985
Volumen: 36
Fascículo: 1
Páginas: 3-11
Tipo: Artículo
Otras publicaciones en: Collectanea mathematica
Resumen
BRANDT [1] gave a structure theorem for connecte groupoids $G$, which in a simplicial version stablishes that $K(\Pi_1\quad (G,^\ast), \thinspace 1)$ is a strong deformation retract of $G$. The main object of this paper is to generalice Brandt's theorem to dimension tow: "If $G$ is a Kan 1-connected 2-hypergroupoid, $K(\Pi_2(G,^\ast), 2)$ is a strong deformation retract of $G$". Then, for a 1-connected topological space $X$ and $^\ast\epsilon X$ the homotopy 2-hypergroupoid of $X$ is equivalent to the second homotopy group $\Pi_2(X,^\ast)$ and the Hurewicz theorem is obtained as an elemental application.