Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The First Stars and Quasars   The first star clusters and quasars resulted directly from the growth of
linear density fluctuations in the early Universe. Since they emerged from a
well-defined set of initial conditions, the interplay between observational
data from the Next Generation Space Telescope (NGST) and theoretical modeling
will advance the current understanding of star and quasar formation. The first
objects had a substantial impact on the thermal and chemical state of the rest
of the Universe as they reionized the intergalactic medium and enriched it with
metals.

2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ