Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Study of Structure Formation and Reheating in the D3/D7 Brane
  Inflation Model   We study the spectrum of cosmological fluctuations in the D3/D7 brane
inflationary universe with particular attention to the parametric excitation of
entropy modes during the reheating stage. The same tachyonic instability which
renders reheating in this model very rapid leads to an exponential growth of
entropy fluctuations during the preheating stage which in turn may induce a
large contribution to the large-scale curvature fluctuations. We take into
account the effects of long wavelength quantum fluctuations in the matter
fields. As part of this work, we perform an analytical analysis of the
reheating process. We find that the initial stage of preheating proceeds by the
tachyonic instability channel. An upper bound on the time it takes for the
energy initially stored in the inflaton field to convert into fluctuations is
obtained by neglecting the local fluctuations produced during the period of
tachyonic decay and analyzing the decay of the residual homogeneous field
oscillations, which proceeds by parametric resonance. We show that in spite of
the fact that the resonance is of narrow-band type, it is sufficiently
efficient to rapidly convert most of the energy of the background fields into
matter fluctuations.

30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci