Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inflation from R^2 gravity: a new approach using nonlinear
  electrodynamics   We discuss another approach regarding the inflation from the R^2 theory of
gravity originally proposed by Starobinski. A non-singular early cosmology is
proposed, where, adding a nonlinear electrodynamics Lagrangian to the
high-order action, a bouncing is present and a power-law inflation is obtained.
In the model the Ricci scalar works like an inflaton field.

6
The categories of this paper are: astro-ph
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The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
18
The categories of this paper are: econ
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The categories of this paper are: hep-th