Solutions for gauged nonlinear Schro<spacing diaeresis>dinger equations on R2 involving sign-changing potentials

This study focused on establishing the existence and multiplicity of solutions for gauged nonlinear Schro<spacing diaeresis>dinger equations set on the plane with sign-changing potentials. Our findings contribute to the extension of recent advancements in this area of research. Initially, we examined scenarios where the potential function V is lower-bounded and the function space has a compact embedding into Lebesgue spaces. Subsequently, we addressed more complex cases characterized by a sign-changing potential V and a function space that fails to compactly embed into Lebesgue spaces. The proofs of our results are based on the Trudinger-Moser inequality, the application of variational methods, and the utilization of Morse theory.