Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Penrose limit and string quantization in AdS_3 \times S^3   We consider corrections to the Penrose limit of AdS_3 \times S^3 with NS-NS
flux which are due to the terms next to leading order in inverse radius
expansion. The worldsheet theory of a lightcone string is interacting due to
the presence of quartic terms in the action. Perturbative corrections to the
spectrum are shown to agree with the results from the exact quantization in
AdS_3 \times S^3.

35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org