The structure of the Boij-Söderberg posets

Author:
David Cook II

Journal:
Proc. Amer. Math. Soc. **139** (2011), 2009-2015

MSC (2010):
Primary 05E45, 06B23, 13C14

Published electronically:
December 1, 2010

MathSciNet review:
2775378

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Abstract | References | Similar Articles | Additional Information

Abstract: Boij and Söderberg made a pair of conjectures, which were subsequently proven by Eisenbud and Schreyer and then extended by Boij and Söderberg, concerning the structure of Betti diagrams of graded modules. In the theory, a particular family of posets and their associated order complexes play an integral role. We explore the structure of this family. In particular, we show that the posets are bounded complete lattices and the order complexes are vertex-decomposable, hence Cohen-Macaulay and squarefree glicci.

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Additional Information

**David Cook II**

Affiliation:
Department of Mathematics, University of Kentucky, 715 Patterson Office Tower, Lexington, Kentucky 40506-0027

Email:
dcook@ms.uky.edu

DOI:
http://dx.doi.org/10.1090/S0002-9939-2010-10791-8

Keywords:
Boij-Söderberg theory,
lattice,
order complex,
vertex-decomposable

Received by editor(s):
June 10, 2010

Published electronically:
December 1, 2010

Additional Notes:
Part of the work for this paper was done while the author was partially supported by the National Security Agency under grant number H98230-09-1-0032.

Communicated by:
Irena Peeva

Article copyright:
© Copyright 2010
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication.