Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scale Invariant Density Perturbations from Cyclic Cosmology   It is shown how quantum fluctuations of the radiation during the contraction
era of a CBE (Comes Back Empty) cyclic cosmology can provide density
fluctuations which re-enter the horizon during the subsequent expansion era and
at lowest order are scale invariant, in a Harrison-Zel'dovich-Peebles sense, as
necessary to be consistent with observations of large scale structure.

16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph