Weak Eigenfunctions for the Linearization of Extremal Elliptic Problems
✍ Scribed by Xavier Cabré; Yvan Martel
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 466 KB
- Volume
- 156
- Category
- Article
- ISSN
- 0022-1236
No coin nor oath required. For personal study only.
✦ Synopsis
We consider the semilinear elliptic problem
where * is a nonnegative parameter and g is a positive, nondecreasing, convex nonlinearity. There exists a value ** of the parameter which is extremal in terms of existence of solution. We study the linearization of the semilinear problem at the extremal weak solution corresponding to the parameter *=**. In some cases, this linearized problem has discrete and positive H 1 0 -spectrum. However, we prove that there always exists a positive weak eigenfunction in L 1 (0) with eigenvalue zero for this linearized problem. The zero L 1 -eigenvalue is coherent with the nonexistence of solutions of the semilinear problem for *>**. Finally, we find all weak eigenfunctions and eigenvalues for the linearization of the extremal problem when 0 is the unit ball and g(u)=e u or g(u)=(1+u) p .
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