Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the abundance of primordial bound states of superheavy magnetic
  monopoles   It has been suggested that superheavy charged particles might have been born
in primordial bound pairs at the end of cosmic inflation. Such pairs have been
proposed as a source of ultra-high energy cosmic rays (UHECR). We show that
primordial bound pairs of magnetic monopoles larger than $10^{-9}$ cm quickly
thermolise due to the interaction with primordial electron-positron plasma and
any such initial primordial concentration is washed out. The final
concentration will therefore be defined by their equilibrium abundance.

29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc