English

Algebraic shifting and exterior and symmetric algebra methods

Commutative Algebra 2007-05-23 v3

Abstract

We establish results about algebraic shifting of simplicial complexes and use them to compare different shifting operations. In particular, we show that each shifting operation does not decrease the number of facets, and that the exterior shift is the best among the exterior shifting operations in the sense that it increases the number of facets the least. Methods of proof include Gr\"obner basis theory over the exterior algebra, Cartan homology, degree functions, and Alexander duality.

Keywords

Cite

@article{arxiv.math/0512521,
  title  = {Algebraic shifting and exterior and symmetric algebra methods},
  author = {Uwe Nagel and Tim Roemer and Natale Paolo Vinai},
  journal= {arXiv preprint arXiv:math/0512521},
  year   = {2007}
}

Comments

26 pages. Revised version. Proofs of theorems 2.10 (now 2.11) and 2.11 (now 2.12) corrected. Exposition improved with some reordering. Minor changes

R2 v1 2026-07-22T17:29:03.786Z