Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A combinatorial model for reversible rational maps over finite fields   We study time-reversal symmetry in dynamical systems with finite phase space,
with applications to birational maps reduced over finite fields. For a
polynomial automorphism with a single family of reversing symmetries, a
universal (i.e., map-independent) distribution function R(x)=1-e^{-x}(1+x) has
been conjectured to exist, for the normalized cycle lengths of the reduced map
in the large field limit (J. A. G. Roberts and F. Vivaldi, Nonlinearity 18
(2005) 2171-2192). We show that these statistics correspond to those of a
composition of two random involutions, having an appropriate number of fixed
points. This model also explains the experimental observation that,
asymptotically, almost all cycles are symmetrical, and that the probability of
occurrence of repeated periods is governed by a Poisson law.

17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th