Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A resolution of the Loschmidt paradox on the Boltzmann H Theorem   A resolution of the Loschmidt paradox on the Boltzmann H theorem is proposed,
based on some new concepts concerning motion backwards in time. The key to this
resolution, taken from our interpretation of motion backwards in time, is the
associated notion of negative mass, attributed to particles moving backwards in
time, which we call retro particles, or simply retrons.

35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
20
The categories of this paper are: acc-phys