Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First Life in the Universe   Here, we ask a simple question, i.e. "at what cosmic time, at the earliest,
did life first appear in the universe?" Given what we know about the universe
today, there may be some partial answers to this question, but much will still
have to be left to speculation. If life in general requires stars as its
primary energy source and uses elemental building blocks heavier than those
initially produced in a Big Bang scenario, first life could have appeared, when
the universe was considerably less than 0.1 billion years old. At that time,
heavy element producing hypernovae exploded at corresponding redshifts.}
$z$\,\gapprox\,45, significantly higher than commonly assumed ($z \approx 6$).
The recent discovery of a galaxy at $z > 9$ could provide supporting evidence
for the hypothesis of a very much shorter time scale than what is widely
believed.

16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph