Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exact hopping and collision times for two hard discs in a box   We study the molecular dynamics of two discs undergoing Newtonian
("inertial") dynamics, with elastic collisions in a rectangular box. Using a
mapping to a billiard model and a key result from ergodic theory, we obtain
exact, analytical expressions for the mean times between the following events:
hops, i.e.~horizontal or vertical interchanges of the particles; wall
collisions; and disc collisions. To do so, we calculate volumes and
cross-sectional areas in the four-dimensional configuration space. We compare
the analytical results against Monte Carlo and molecular dynamics simulations,
with excellent agreement.

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The categories of this paper are: chem-ph
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ex
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The categories of this paper are: stat
12
The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: physics
0
The categories of this paper are: hep-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: econ