Characters of fundamental groups of curve complements and orbifold pencils

  • Enrique Artal Bartolo
  • Jose Ignacio Cogolludo-Agustín
  • Anatoly Libgober
Conference paper
Part of the CRM Series book series (PSNS)


The present work is a user’s guide to the results of [7], where a description of the space of characters of a quasi-projective variety was given in terms of global quotient orbifold pencils.

Below we consider the case of plane curve complements. In particular, an infinite family of curves exhibiting characters of any torsion and depth 3 will be discussed. Also, in the context of line arrangements, it will be shown how geometric tools, such as the existence of orbifold pencils, can replace the group theoretical computations via fundamental groups when studying characters of finite order, specially order two. Finally, we revisit an Alexander-equivalent Zariski pair considered in the literature and show how the existence of such pencils distinguishes both curves.


Fundamental Group Irreducible Component Characteristic Variety Alexander Polynomial Orbifold Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Scuola Normale Superiore Pisa 2012

Authors and Affiliations

  • Enrique Artal Bartolo
  • Jose Ignacio Cogolludo-Agustín
  • Anatoly Libgober

There are no affiliations available

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