Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Review on High energy String Scattering Amplitudes and Symmetries of
  String Theory   We review high energy symmetries of string theory at both the fixed angle or
Gross regime (GR) and the fixed momentum transfer or Regge regime (RR). We
calculated in details high energy string scattering amplitudes at arbitrary
mass levels for both regimes. We discovered infinite linear relations among
fixed angle string amplitudes conjectured by Gross in 1988 from decoupling of
high energy zero-norm states (ZNS), and infinite recurrence relations among
Regge string amplitudes from Kummer function U and Appell function F_1.
However, the linear relations we obtained in the GR corrected [27-32] the
saddle point calculations of Gross, Gross and Mende and Gross and Manes [1-5].
Our results were consistent with the decoupling of high energy ZNS or unitarity
of the theory while those of them were not. In addition, for the case of high
energy closed string scatterings, our results [36] differ from theirs by an
oscillating prefactor which was crucial to recover the KLT relation valid for
all energies. In the GR/RR regime, all high energy string amplitudes can be
solved by these linear/recurrence relations so that all GR/RR string amplitudes
can be expressed in terms of one single GR/RR string amplitude. In addition, we
found an interesting link between string amplitudes of the two regimes, and
discovered that at each mass level the ratios among fixed angle amplitudes can
be extracted from Regge string scattering amplitudes. This result enables us to
argue that the known SL(5,C) dynamical symmetry of the Appell function F_1 is
crucial to probe high energy spacetime symmetry of string theory.

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The categories of this paper are: atom-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs