Special Session 17: 

Positivity of bifurcating solutions of indefinite concave-convex problems

Kenichiro Umezu
Ibaraki University
Japan
Co-Author(s):    Uriel Kaufmann, Humberto Ramos Quoirin
Abstract:
In this talk, we consider semilinear elliptic equations of indefinite concave-convex type with Dirichlet and Neumann boundary conditions and prove the existence of loop components of nonnegative solutions bifurcating from a trivial line in some cases. Positivity of nontrivial nonnegative solutions on the loops is also studied by use of a continuation argument.