We prove a decomposition theorem for the cd-index of a Gorenstein * poset analogous to the decomposition theorem for the intersection cohomology of a toric variety. From this we settle a conjecture of Stanley that the cd-index of Gorenstein* lattices is minimized on Boolean algebras.
|Number of pages||27|
|Journal||Journal of Algebraic Combinatorics|
|State||Published - Sep 2007|
Bibliographical noteFunding Information:
Acknowledgments The first author thanks Mittag-Leffler Institute where part of this research was carried out. He was also supported by NSF Grant DMS-0200624. The second author was supported by NSERC grant RGPIN 283301.
- Decomposition theorem
- Gorenstein* posets
ASJC Scopus subject areas
- Algebra and Number Theory
- Discrete Mathematics and Combinatorics