Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: What is String Theory?   The first part is an introduction to conformal field theory and string
perturbation theory. The second part deals with the search for a deeper answer
to the question posed in the title. Contents:
  1. Conformal Field Theory
  2. String Theory
  3. Vacua and Dualities
  4. String Field Theory or Not String Field Theory
  5. Matrix Models

31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn