Orbifold groups, quasi-projectivity and covers

Autor:	Bartolo, Enrique Artal, Cogolludo-Agustin, Jose Ignacio, Matei, Daniel
Rok vydání:	2012
Předmět:	Mathematics - Algebraic Geometry Mathematics - Geometric Topology 14H30 57R18 55N25
Druh dokumentu:	Working Paper
Popis:	We discuss properties of complex algebraic orbifold groups, their characteristic varieties, and their abelian covers. In particular, we deal with the question of (quasi)-projectivity of orbifold groups. We also prove a structure theorem for the variety of characters of normal-crossing quasi-projective orbifold groups. Finally, we extend Sakuma's formula for the first Betti number of abelian covers of orbifold fundamental groups. Several examples are presented, including a compact orbifold group which is not projective and a Zariski pair of plane projective curves that can be told by considering an unbranched cover of the projective plane with an orbifold structure. Comment: 20 pages
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1203.1645 Zobrazit plný text záznamu View this record from Arxiv