Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Homotopy classes of harmonic maps of the stratified 2-spheres and
  applications to geometric flows   We show that the set of harmonic maps from the 2-dimensional stratified
spheres with uniformly bounded energies contains only finitely many homotopy
classes. We apply this result to construct infinitely many harmonic map flows
and mean curvature flows of 2-sphere in the connected sum of two closed
3-dimensional manifolds $M_1\not=S^3$ and $M_2\not=S^3,\R\P^3$, which must
develop finite time singularity.

28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th