Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Null Energy Condition Violations in Eternal Inflation   The usual scenario of ``eternal inflation'' involves an approximately de
Sitter spacetime undergoing upward fluctuations of the local expansion rate
$H$. This spacetime requires frequent violations of the Null Energy Condition
(NEC). We investigate the fluctuations of the energy-momentum tensor of the
scalar field in de Sitter space as a possible source of such violations. We
find that fluctuations of the energy-momentum tensor smeared in space and time
are well-defined and may provide the NEC violations. Our results for slow-roll
inflation are consistent with the standard calculations of inflationary density
fluctuations. In the diffusive regime where quantum fluctuations dominate the
slow-roll evolution, the magnitude of smeared energy-momentum tensor
fluctuations is large enough to create frequent NEC violations.

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The categories of this paper are: hep-th
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
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The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
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The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio