English

Generalized parabolic structures over smooth curves with many components and principal bundles over reducible nodal curves

Algebraic Geometry 2020-07-28 v2

Abstract

Let Y1,,YlY_{1},\dots,Y_{l} be smooth irreducible projective curves and let YY be its disjoint union. Given a semisimple reductive algebraic group GG and a faithful representation ρ:GSL(V)\rho:G\hookrightarrow \textrm{SL}(V) we construct a projective moduli space of (κ,δ)(\underline{\kappa},\delta)-(semi)stable singular principal GG-bundles with generalized parabolic structure of type e\underline{e}. In case YY is the normalization of a connected and reducible projective nodal curve XX, there is a closed subscheme coarsely representing the subfunctor corresponding to descending bundles. We prove that the descent operation induces a birational, surjective and proper morphism onto the schematic closure of the space of δ\delta-stable singular principal GG-bundles whose associated torsion free sheaf is of local type e\underline{e}.

Keywords

Cite

@article{arxiv.1910.13403,
  title  = {Generalized parabolic structures over smooth curves with many components and principal bundles over reducible nodal curves},
  author = {Ángel Luis Muñoz Castañeda},
  journal= {arXiv preprint arXiv:1910.13403},
  year   = {2020}
}