Sur les équations d'évolution non linéaires 1
Surjectivity results of Fredholm alternative type are obtained for nonlinear operator equations of the form , where is invertible, and satisfy various types of homogeneity conditions. We are able to answer some questions left open by Fuč’ık, Nečas, Souček, and Souček. We employ the concept of an -stably-solvable operator, related to nonlinear spectral theory methodology. Applications are given to a nonlinear Sturm-Liouville problem and a three point boundary value problem recently studied...
We study a coincidence problem of the form A(x) ∈ ϕ (x), where A is a linear Fredholm operator with nonnegative index between Banach spaces and ϕ is a multivalued A-fundamentally contractible map (in particular, it is not necessarily compact). The main tool is a coincidence index, which becomes the well known Leray-Schauder fixed point index when A=id and ϕ is a compact singlevalued map. An application to boundary value problems for differential equations in Banach spaces is given.
The existence of bounded solutions for equations x' = A(t)x + r(x,t) is proved, where the linear part is exponentially dichotomic and the nonlinear term r satisfies some weak conditions.
The existence of solutions is studied for certain nonlinear differential equations with both linear and nonlinear conditions