## Topological Methods in Nonlinear Analysis

### On the suspension isomorphism for index braids in a singular perturbation problem

#### Abstract

We consider the singularly perturbed system of ordinary differential equations $$\begin{split} \varepsilon\dot y&=f(y,x,\varepsilon), \\ \dot x&=h(y,x,\varepsilon) \end{split} \tag{(E_\varepsilon)}$$ on $Y\times \mathcal{M}$, where $Y$ is a finite dimensional normed space and $\mathcal{M}$ is a smooth manifold. We assume that there is a reduced manifold of $(E_\varepsilon)$ given by the graph of a function $\phi\colon \mathcal{M}\to Y$ and satisfying an appropriate hyperbolicity assumption with unstable dimension $k\in{\mathbb N}_0$. We prove that every Morse decomposition $(M_p)_{p\in P}$ of a compact isolated invariant set $S_0$ of the reduced equation $$\dot x=h(\phi(x),x,0)$$ gives rises, for $\varepsilon> 0$ small, to a Morse decomposition $(M_{p,\varepsilon})_{p\in P}$ of an isolated invariant set $S_\varepsilon$ of $(E_\varepsilon)$ such that $(S_\varepsilon,(M_{p,\varepsilon})_{p\in P})$ is close to $(\{0\}\times S_0,(\{0\}\times M_p)_{p\in P})$ and the (co)homology index braid of $(S_\varepsilon,(M_{p,\varepsilon})_{p\in P})$ is isomorphic to the (co)homology index braid of $(S_0,(M_{p})_{p\in P})$ shifted by $k$ to the left.

#### Article information

Source
Topol. Methods Nonlinear Anal., Volume 32, Number 2 (2008), 199-225.

Dates
First available in Project Euclid: 13 May 2016

https://projecteuclid.org/euclid.tmna/1463151164

Mathematical Reviews number (MathSciNet)
MR2494055

Zentralblatt MATH identifier
1188.34070

#### Citation

Carbinatto, Maria C.; Rybakowski, Krzysztof P. On the suspension isomorphism for index braids in a singular perturbation problem. Topol. Methods Nonlinear Anal. 32 (2008), no. 2, 199--225. https://projecteuclid.org/euclid.tmna/1463151164

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