Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Simple Derivation of Supersymmetric Extremal Black Hole Attractors   We present a simple and yet rigorous derivation of the flow equations for the
supersymmetric black-hole solutions of all 4-dimensional supergravities based
on the recently found general form of all those solutions.

18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin