Say I have a family of linear spaces, and that I can solve all Schuber problems of that family (that is, how many members of the family pass through a set $S$ of linear spaces, whe …

Both Kazhdan-Lusztig and Steinberg have defined pairs of preorders on $S_n$. Kazhdan and Lusztig's preorders come from their basis: We write $x\leq_L y$ if any left ideal span …

Let $G(n, X)$ be the set of all $n$-dim subspaces of a $n+m$-dim vector space $X$. $$ 0=F_0 \subset F_1 \subset \cdots \subset F_{n+m-1} \subset F_{n+m} = X $$ is a fixed compl …

Consider a smooth, closed, compact finite-dim manifold. We have Poincare Duality to relate the cocycles and cycles. I would like to know where I can find a reference for a pr …