Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An elementary proof of Small's formula for null curves in PSL(2,C) and
  an analogue for Legendrian curves in PSL(2,C)   For null curves in PSL(2,C), there exists a representation formula in terms
of two meromorphic functions and their derivatives (Small's formula). In this
paper, we give an elementary proof of Small's formula. Moreover, a similar
formula for Legendrian curves in PSL(2,C) is given. As null curves in PSL(2,C)
are related to mean curvature one surfaces in hyperbolic 3-space H^3,
Legendrian curves are related to flat surfaces in H^3. So, as an application of
Small-type formula for Lengendrian curves, we give new examples of flat
surfaces in H^3.

27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
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The categories of this paper are: supr-con
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs