Conley index in Hilbert spaces and a problem of Angenent and van der Vorst

• Autorzy: Marek Izydorek , Krzysztof P. Rybakowski
• Języki publikacji: EN

Abstrakty

EN

In a recent paper [9] we presented a Galerkin-type Conley index theory for certain classes of infinite-dimensional ODEs without the uniqueness property of the Cauchy problem. In this paper we show how to apply this theory to strongly indefinite elliptic systems. More specifically, we study the elliptic system
$-Δu = ∂_{v}H(u,v,x)$ in Ω,
$-Δv = ∂_{u}H(u,v,x)$ in Ω,
u = 0, v = 0 in ∂Ω, (A1)
on a smooth bounded domain Ω in $ℝ^{N}$ for "-"-type Hamiltonians H of class C² satisfying subcritical growth assumptions on their first order derivatives. As shown by Angenent and van der Vorst in [1], the solutions of (A1) are equilibria of an abstract ordinary differential equation
ż = f(z) (A2)
defined on a certain Hilbert space E of functions z = (u,v). The map f: E → E is continuous, but, in general, not differentiable nor even locally Lipschitzian.
The main result of this paper is a Linearization Principle which states that whenever z₀ is a hyperbolic equilibrium of (A2) then the Conley index of {z₀} can be computed by formally linearizing (A2) at z₀.
As a particular application of the Linearization Principle we obtain an elementary, Conley index based proof of the existence of nontrivial solutions of (A1), a result previously established in [1] via Morse-Floer homology.
Further applications of our method to existence and multiplicity results for strongly indefinite systems appear in [3] and [10].

Kategorie tematyczne

• 47J35: Nonlinear evolution equations
• 58E05: Abstract critical point theory (Morse theory, Ljusternik-Schnirelman (Lyusternik-Shnirel\cprime man) theory, etc.)
• 37B30: Index theory, Morse-Conley indices
• 34G20: Nonlinear equations

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Fundamenta Mathematicae
• Rocznik: 2002
• Tom: 173
• Numer: 1
• Strony: 77-100

Daty

wydano

2002

Twórcy

autor

Marek Izydorek

• Technical University Gdańsk, Faculty of Technical Physics and Applied Mathematics, Narutowicza 11/12, 80-952 Gdańsk, Poland

autor

Krzysztof P. Rybakowski

• Fachbereich Mathematik, Universität Rostock, Universitätsplatz 1, 18055 Rostock, Germany

Identyfikatory

DOI

10.4064/fm173-1-5