English

On the Ext algebras of parabolic Verma modules and A infinity-structures

Representation Theory 2011-06-28 v1 Symplectic Geometry

Abstract

We study the Ext-algebra of the direct sum of all parabolic Verma modules in the principal block of the Bernstein-Gelfand-Gelfand category O for the hermitian symmetric pair (gln+m,glnglm)(\mathfrak{gl}_{n+m}, \mathfrak{gl}_{n} \oplus \mathfrak{gl}_m) and present the corresponding quiver with relations for the cases n=1, 2. The Kazhdan-Lusztig combinatorics is used to deduce a general vanishing result for the higher multiplications in the A infinity-structure of a minimal model. An explicit example of the higher multiplications with non-vanishing m3m_3 is included.

Keywords

Cite

@article{arxiv.1106.5406,
  title  = {On the Ext algebras of parabolic Verma modules and A infinity-structures},
  author = {Angela Klamt and Catharina Stroppel},
  journal= {arXiv preprint arXiv:1106.5406},
  year   = {2011}
}

Comments

This article is based on arXiv:1104.0102 and focuses on presenting the main results and techniques; Journal of Pure and Applied Algebra, 2011