Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlocal aspects of $\lambda$-symmetries and ODEs reduction   A reduction method of ODEs not possessing Lie point symmetries makes use of
the so called $\lambda$-symmetries (C. Muriel and J. L. Romero, \emph{IMA J.
Appl. Math.} \textbf{66}, 111-125, 2001). The notion of covering for an ODE
$\mathcal{Y}$ is used here to recover $\lambda$-symmetries of $\mathcal{Y}$ as
nonlocal symmetries. In this framework, by embedding $\mathcal{Y}$ into a
suitable system $\mathcal{Y}^{\prime}$ determined by the function $\lambda$,
any $\lambda$-symmetry of $\mathcal{Y}$ can be recovered by a local symmetry of
$\mathcal{Y}^{\prime}$. As a consequence, the reduction method of Muriel and
Romero follows from the standard method of reduction by differential invariants
applied to $\mathcal{Y}^{\prime}$.

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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph