Proceedings of the Royal Society of Edinburgh: Section A Mathematics

Research Article

Bifurcation results for semilinear elliptic problems in RN

Marino Badialea1 and Alessio Pomponioa2

a1 Dipartimento di Matematica, Università di Torino, Via Carlo Alberto 10, 10123 Torino, Italy (

a2 SISSA, via Beirut 2–4, 34014 Trieste, Italy (


In this paper we obtain, for a semilinear elliptic problem in RN, families of solutions bifurcating from the bottom of the spectrum of −Δ. The problem is variational in nature and we apply a nonlinear reduction method that allows us to search for solutions as critical points of suitable functionals defined on finite-dimensional manifolds.

(Received January 22 2003)

(Accepted June 30 2003)