Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Metric Perturbations in Dilaton-Driven Inflation   We compute the spectrum of scalar and tensor metric perturbations generated,
as amplified vacuum fluctuations, during an epoch of dilaton-driven inflation
of the type occurring naturally in string cosmology. In the tensor case the
computation is straightforward while, in the scalar case, it is made delicate
by the appearance of a growing mode in the familiar longitudinal gauge. In
spite of this, a reliable perturbative calculation of perturbations far outside
the horizon can be performed by resorting either to appropriate gauge invariant
variables, or to a new coordinate system in which the growing mode can be
"gauged down". The simple outcome of this complicated analysis is that both
scalar and tensor perturbations exhibit nearly Planckian spectra, whose common
"temperature" is related to some very basic parameters of the string-cosmology
background.

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The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: dg-ga
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The categories of this paper are: stat
3
The categories of this paper are: physics