Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Review of Spectroscopic Determination of Extra Spatial Dimensions in the
  Early Universe   Atomic and molecular transitions for high Z objects in the early universe
give bounds to the possible existence of extra spatial dimensions $D =
3+\epsilon$. We review the theory and present observational data, based on
Lyman and Balmer hydrogen transitions of distant quasars and CO rotational
transitions of far away giant molecular clouds.

24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
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The categories of this paper are: econ
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat