Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Can the scale factor be rippled?   We address an issue: would the cosmological scale factor be a locally
oscillating quantity? This problem is examined in the framework of two
classical 1+1-dimensional models: the first one is a string against a curved
background, and the second one is an inhomogeneous Bianchi I model. For the
string model, it is shown that there exist the gauge and the initial condition
providing an oscillation of scale factor against a slowly evolving background,
which is not affected by such an oscillation "at the mean". For the
inhomogeneous Bianchi I model with the conformal time gauge, an initially
homogeneous scale factor can become inhomogeneous and undergo the nonlinear
oscillations. As is shown these nonlinear oscillations can be treated as a
nonlinear gauge wave.

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The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn