Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermal and Non-Thermal Production of Gravitinos in the Early Universe   The excessive production of gravitinos in the early universe destroys the
successful predictions of nucleosynthesis. The thermal generation of gravitinos
after inflation leads to the bound on the reheating temperature, T_{RH}< 10^9
GeV. However, it has been recently realized that the non-thermal generation of
gravitinos in the early universe can be extremely efficient and overcome the
thermal production by several orders of magnitude, leading to much tighter
constraints on the reheating temperature. In this paper, we first investigate
some aspects of the thermal production of gravitinos, taking into account that
in fact reheating is not instantaneous and inflation is likely to be followed
by a prolonged stage of coherent oscillations of the inflaton field. We then
proceed by further investigating the non-thermal generation of gravitinos,
providing the necessary tools to study this process in a generic time-dependent
background with any number of superfields. We also present the first numerical
results regarding the non-thermal generation of gravitinos in particular
supersymmetric models.

26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
27
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