A note on the topological degree at a critical point of mountainpass-type

Author:
Helmut Hofer

Journal:
Proc. Amer. Math. Soc. **90** (1984), 309-315

MSC:
Primary 58E05; Secondary 47H15

DOI:
https://doi.org/10.1090/S0002-9939-1984-0727256-0

MathSciNet review:
727256

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Abstract | References | Similar Articles | Additional Information

Abstract: In this note we will show that the local degree at an isolated critical point given by the Ambrosetti-Rabinowitz mountainpass-theorem is for a large class of functionals. This class includes for example those functionals arising in the study of second order elliptic equations.

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1984-0727256-0

Keywords:
Critical point theory,
Leray-Schauder degree,
nonlinear functional analysis

Article copyright:
© Copyright 1984
American Mathematical Society