Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morphisms between Grassmannians   Denote by $\mathbb G(k,n)$ the Grassmannian of linear subspaces of dimension
$k$ in $\mathbb P^n$. We show that if $n>m$ then every morphism $\varphi:
\mathbb G(k,n) \to \mathbb G(l,m)$ is constant.

12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc