Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Illustrated Introduction to the Ricci Flow   The Ricci flow is one of the most important topics in differential geometry,
and a central focus of modern geometric analysis. In this paper, we give an
illustrated introduction to the subject which is intended for a general
audience. The goal is to provide a working definition of the Ricci flow as well
as some intuition for its behavior without assuming any prerequisite knowledge
of differential geometry or topology.

18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con