Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum fluctuations in brane-world inflation without inflaton on the
  brane   A Randall-Sundrum type brane-cosmological model in which slow-roll inflation
on the brane is driven solely by a bulk scalar field was recently proposed by
Himemoto and Sasaki. We analyze their model in detail and calculate the quantum
fluctuations of the bulk scalar field $\phi$ with $m^2=V''(\phi)$. We decompose
the bulk scalar field into the infinite mass spectrum of 4-dimensional fields;
the field with the smallest mass-square, called the zero-mode, and the
Kaluza-Klein modes above it with a mass gap. We find the zero-mode dominance of
the classical solution holds if $|m^2|\bar\ell^2\ll1$, where $\bar{\ell}$ is
the curvature radius of the effectively anti-de Sitter bulk, but it is violated
if $|m^2|\bar\ell^2\gg1$, though the violation is very small. Then we evaluate
the vacuum expectation value $<\delta\phi^2>$ on the brane. We find the
zero-mode contribution completely dominates if $|m^2|\bar{\ell}^2\ll 1$ similar
to the case of classical background. In contrast, we find the Kaluza-Klein
contribution is small but non-negligible if the value of $|m^2|\bar{\ell}^2$ is
large.

8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th