Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-linear relativistic perturbation theory with two parameters   An underlying fundamental assumption in relativistic perturbation theory is
the existence of a parametric family of spacetimes that can be Taylor expanded
around a background. Since the choice of the latter is crucial, sometimes it is
convenient to have a perturbative formalism based on two (or more) parameters.
A good example is the study of rotating stars, where generic perturbations are
constructed on top of an axisymmetric configuration built by using the slow
rotation approximation. Here, we discuss the gauge dependence of non-linear
perturbations depending on two parameters and how to derive explicit higher
order gauge transformation rules.

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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
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The categories of this paper are: eess
12
The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
2
The categories of this paper are: math
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The categories of this paper are: econ
35
The categories of this paper are: mtrl-th