Stability of gradient semigroups under perturbations

Author(s)

Aragao-Costa, E. R. ^[1] ; Caraballo, T. ^[2] ; Carvalho, A. N. ^[1] ; Langa, J. A. ^[2]

Affiliation

^[1] Univ Sao Paulo Campus Sao Carlos, Inst Ciencias Matemat & Comp, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Seville, Dept Ecuac Diferenciales & Anal Numer, E-41080 Seville - Spain

• Document type: Journal article
• Source: Nonlinearity; v. 24, n. 7, p. 2099-2117, JUL 2011.
• Web of Science Citations: 24

Abstract

In this paper we prove that gradient-like semigroups (in the sense of Carvalho and Langa (2009 J. Diff. Eqns 246 2646-68)) are gradient semigroups (possess a Lyapunov function). This is primarily done to provide conditions under which gradient semigroups, in a general metric space, are stable under perturbation exploiting the known fact (see Carvalho and Langa (2009 J. Diff. Eqns 246 2646-68)) that gradient-like semigroups are stable under perturbation. The results presented here were motivated by the work carried out in Conley (1978 Isolated Invariant Sets and the Morse Index (CBMS Regional Conference Series in Mathematics vol 38) (RI: American Mathematical Society Providence)) for groups in compact metric spaces (see also Rybakowski (1987 The Homotopy Index and Partial Differential Equations (Universitext) (Berlin: Springer)) for the Morse decomposition of an invariant set for a semigroup on a compact metric space). (AU)