TY - JOUR

T1 - 8.—Bifurcation and Asymptotic Bifurcation for Non-compact Non-symmetric Gradient Operators

AU - Toland, J. F.

PY - 1975/1/1

Y1 - 1975/1/1

N2 - The first part of this paper is devoted to a study of the classical bifurcation problem in a Hilbert space, under the assumption that the operators involved are gradient operators, but not necessarily compact. Our approach to the problem was introduced by Krasnosel'skii, but here we show that his assumption about the compactness of the operators can be replaced by a much weaker Lipschitz type condition, without affecting the generality of his conclusions. The rest of the paper is concerned with the analogous problem when the operator is known to be asymptotically linear rather than Frechet differentiable. Indeed, we show that this question can always be reduced to the first case, after some manipulation. After this manipulation the new operator is found to be a Frechet differentiable gradient operator, and so we can invoke the results of the first part. This manipulation is in the spirit of that of [11] but is necessarily different.

AB - The first part of this paper is devoted to a study of the classical bifurcation problem in a Hilbert space, under the assumption that the operators involved are gradient operators, but not necessarily compact. Our approach to the problem was introduced by Krasnosel'skii, but here we show that his assumption about the compactness of the operators can be replaced by a much weaker Lipschitz type condition, without affecting the generality of his conclusions. The rest of the paper is concerned with the analogous problem when the operator is known to be asymptotically linear rather than Frechet differentiable. Indeed, we show that this question can always be reduced to the first case, after some manipulation. After this manipulation the new operator is found to be a Frechet differentiable gradient operator, and so we can invoke the results of the first part. This manipulation is in the spirit of that of [11] but is necessarily different.

UR - http://www.scopus.com/inward/record.url?scp=84975965978&partnerID=8YFLogxK

U2 - 10.1017/S0308210500016334

DO - 10.1017/S0308210500016334

M3 - Article

AN - SCOPUS:84975965978

VL - 73

SP - 137

EP - 147

JO - Proceedings of the Royal Society of Edinburgh Section A - Mathematics

JF - Proceedings of the Royal Society of Edinburgh Section A - Mathematics

SN - 0308-2105

ER -