Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Slow and Safe Gravitinos   It has been argued that supergravity models of inflation with vanishing sound
speeds, $c_s$, lead to an unbounded growth in the production rate of
gravitinos. We consider several models of inflation to delineate the conditions
for which $c_s = 0$. In models with unconstrained superfields, we argue that
the mixing of the goldstino and inflatino in a time-varying background prevents
the uncontrolled production of the longitudinal modes. This conclusion is
unchanged if there is a nilpotent field associated with supersymmetry breaking
with constraint ${\bf S^2} =0$, i.e. sgoldstino-less models. Models with a
second orthogonal constraint, ${\bf S(\Phi-\bar{\Phi})} =0$, where $\bf{\Phi}$
is the inflaton superfield, which eliminates the inflatino, may suffer from the
over-production of gravitinos. However, we point out that these models may be
problematic if this constraint originates from a UV Lagrangian, as this may
require using higher derivative operators. These models may also exhibit other
pathologies such as $c_s > 1$, which are absent in theories with the single
constraint or unconstrained fields.

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The categories of this paper are: econ
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
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The categories of this paper are: nlin
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The categories of this paper are: q-bio