Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The physics and identity of dark matter   This paper follows "The physics and identity of Dark Energy", which is the
acceleration energy of old photons. The present paper considers everything else
in the decay of our universe; it is an ensemble called "old protons, etc."; the
ensemble will be listed. The accelerated expansion of our universe brings the
decay debris into the inter-universal medium (IUM) of the multiverse, where it
is conserved during long times. Debris clouds eventually accrete from the IUM
and grow into proto-universes. The protons, etc. are involved as much as are
the photons; they are the receivers of the kinetic energy of photon
acceleration. Dark matter is therefore the matter of "old protons,etc."
mentioned before.

31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th