Mathematics – Algebraic Topology
Scientific paper
2001-12-14
Duke Math. J. 119 (2003), no. 2, 221--260
Mathematics
Algebraic Topology
30 pages, 21 figures
Scientific paper
We generalize our puzzle formula for ordinary Schubert calculus on Grassmannians, to a formula for the T-equivariant Schubert calculus. The structure constants to be calculated are polynomials in {y_{i+1} - y_i}; they were shown (abstractly) to have positive coefficients in [Graham] math.AG/9908172. Our formula is the first to be manifestly positive in this sense. In particular this gives a new and self-contained proof of the ordinary puzzle formula, by an induction backwards from the "most equivariant" case. The proof of the formula is mostly combinatorial, but requires no prior combinatorics, and only a modicum of equivariant cohomology (which we include). This formula is closely related to the one in [Molev-Sagan] q-alg/9707028 for multiplying factorial Schur functions in three sets of variables, although their rule does not give a positive formula in the sense of [Graham]. We include a cohomological interpretation of this problem, and a puzzle formulation for it.
Knutson Allen
Tao Terence
No associations
LandOfFree
Puzzles and (equivariant) cohomology of Grassmannians does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Puzzles and (equivariant) cohomology of Grassmannians, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Puzzles and (equivariant) cohomology of Grassmannians will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-345325