English

Combinatorial symbolic powers

Commutative Algebra 2007-09-06 v3 Combinatorics

Abstract

Symbolic powers are studied in the combinatorial context of monomial ideals. When the ideals are generated by quadratic squarefree monomials, the generators of the symbolic powers are obstructions to vertex covering in the associated graph and its blowups. As a result, perfect graphs play an important role in the theory, dual to the role played by perfect graphs in the theory of secants of monomial ideals. We use Gr\"obner degenerations as a tool to reduce questions about symbolic powers of arbitrary ideals to the monomial case. Among the applications are a new, unified approach to the Gr\"obner bases of symbolic powers of determinantal and Pfaffian ideals.

Keywords

Cite

@article{arxiv.math/0608542,
  title  = {Combinatorial symbolic powers},
  author = {Seth Sullivant},
  journal= {arXiv preprint arXiv:math/0608542},
  year   = {2007}
}

Comments

29 pages, 3 figures, Positive characteristic results incorporated into main body of paper