Existence and multiplicity of radial sign-changing solutions for the Schrödinger–Born–Infeld system

This paper is concerned with the existence and multiplicity of radial sign-changing solutions for a Schrödinger–Born–Infeld system in R 3 , involving a general subcritical nonlinearity f ( u ) . By employing variational methods, specifically the method of invariant sets of a descending flow, we establish the existence of at least one such solution under a general set of assumptions on f . Furthermore, when the nonlinearity f is odd, we prove that the system admits a sequence of radial sign-changing solutions whose energies are unbounded.