Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Normal-normal resonances in a double Hopf bifurcation   We investigate the stability loss of invariant n-dimensional quasi-periodic
tori during a double Hopf bifurcation, where at bifurcation the two normal
frequencies are in normal-normal resonance. Invariants are used to analyse the
normal form approximations in a unified manner. The corresponding dynamics form
a skeleton for the dynamics of the original system. Here both normal
hyperbolicity and KAM theory are being used.

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The categories of this paper are: q-fin
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol