Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The topology of Birkhoff varieties   Our main theorem is that the inclusion of a Birkhoff variety in the affine
Grassmannian is a homotopy equivalence. We also construct analogues of tubular
neighborhoods for Birkhoff and Schubert varieties. We include some observations
on torus-equivariant cohomology.

31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an