Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reversibility in the diffeomorphism group of the real line   An element of a group is said to be reversible if it is conjugate to its
inverse. We characterise the reversible elements in the group of
diffeomorphisms of the real line, and in the subgroup of order preserving
diffeomorphisms.

24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph