Book contents
- Frontmatter
- Contents
- Preface
- Introduction
- Chapter 1 Lipschitz and Smooth Perturbed Minimization Principles
- Chapter 2 Linear and Plurisubharmonic Perturbed Minimization Principles
- Chapter 3 The Classical Min-Max Theorem
- Chapter 4 A Strong Form of the Min-Max Principle
- Chapter 5 Relaxed Boundary Conditions in the Presence of a Dual Set
- Chapter 6 The Critical Set in the Mountain Pass Theorem
- Chapter 7 Group Actions and Multiplicity of Critical Points
- Chapter 8 The Palais-Smale Condition Around a Dual Set – Examples
- Chapter 9 Morse Indices of Min-Max Critical Points – The Non Degenerate Case
- Chapter 10 Morse Indices of Min-Max Critical Points – The Degenerate Case
- Chapter 11 Morse-type Information on Palais-Smale Sequences
- Appendices by David Robinson
- A Relevant function spaces and inequalities
- B Variational formulations of some boundary value problems
- C The blowing-up of singularities
- D Elements of degree theory
- E Basic properties of martingales
- References
- Index
A - Relevant function spaces and inequalities
Published online by Cambridge University Press: 18 December 2009
- Frontmatter
- Contents
- Preface
- Introduction
- Chapter 1 Lipschitz and Smooth Perturbed Minimization Principles
- Chapter 2 Linear and Plurisubharmonic Perturbed Minimization Principles
- Chapter 3 The Classical Min-Max Theorem
- Chapter 4 A Strong Form of the Min-Max Principle
- Chapter 5 Relaxed Boundary Conditions in the Presence of a Dual Set
- Chapter 6 The Critical Set in the Mountain Pass Theorem
- Chapter 7 Group Actions and Multiplicity of Critical Points
- Chapter 8 The Palais-Smale Condition Around a Dual Set – Examples
- Chapter 9 Morse Indices of Min-Max Critical Points – The Non Degenerate Case
- Chapter 10 Morse Indices of Min-Max Critical Points – The Degenerate Case
- Chapter 11 Morse-type Information on Palais-Smale Sequences
- Appendices by David Robinson
- A Relevant function spaces and inequalities
- B Variational formulations of some boundary value problems
- C The blowing-up of singularities
- D Elements of degree theory
- E Basic properties of martingales
- References
- Index
Summary
Sobolev Spaces
Sobolev spaces are, roughly speaking, spaces of p-integrable functions whose derivatives are also p-integrable. There are two basic types of Sobolev spaces we wish to consider. In the first situation, we have a bounded domain Ω ⊂ ℝN and we consider functions u : Ω → ℝ for which u ≡ 0 on ∂Ω. In the second, we look at functions u : [0, T] → ℝN satisfying u(0) = u(T). The only problem in straightforwardly defining these spaces is that p-integrable functions need not be differentiate and restricting our attention to those that are differentiate does not provide us with what we want — the resulting spaces are not complete. We must weaken our notion of differentiability.
Definition A.1. In the following two cases we define an appropriate notion of weak differentiability.
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- Information
- Duality and Perturbation Methods in Critical Point Theory , pp. 224 - 232Publisher: Cambridge University PressPrint publication year: 1993