The puzzle conjecture for the cohomology of two-step flag manifolds
The puzzle conjecture for the cohomology of two-step flag manifolds
复制标题
两步旗流形上同调的谜题猜想
DOI:
10.1007/s10801-016-0697-3
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发表时间:
2014
影响因子:
0.8
通讯作者:
Harry Tamvakis
中科院分区:
文献类型:
--
作者:
A. Buch;A. Kresch;K. Purbhoo;Harry Tamvakis
We prove a conjecture of Knutson asserting that the Schubert structure constants of the cohomology ring of a two-step flag variety are equal to the number of puzzles with specified border labels that can be created using a list of eight puzzle pieces. As a consequence, we obtain a puzzle formula for the Gromov–Witten invariants defining the small quantum cohomology ring of a Grassmann variety of type A. The proof of the conjecture proceeds by showing that the puzzle formula defines an associative product on the cohomology ring of the two-step flag variety. It is based on an explicit bijection of gashed puzzles that is analogous to the jeu de taquin algorithm but more complicated.