Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The S-matrix algebra of the AdS2 X S2 superstring   In this paper we find the Yangian algebra responsible for the integrability
of the AdS2 X S2 X T^6 superstring in the planar limit. We demonstrate the
symmetry of the corresponding exact S-matrix in the massive sector, including
the presence of the secret symmetry. We give two alternative presentations of
the Hopf algebra, along with related discussions on the issue of evaluation
representations. We study the classical r-matrix, and re-discover the need for
a secret symmetry also in this context. Finally, taking the simplifying
zero-coupling limit of the S-matrix as a generating R-matrix for the Algebraic
Bethe Ansatz, we obtain an effective model of free fermions on a periodic
spin-chain. This limit should provide hints to the one-loop anomalous dimension
of the mysterious superconformal quantum mechanics dual to the superstring
theory in this geometry.

9
The categories of this paper are: nlin
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The categories of this paper are: eess
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph