Keywords: indefinite and unbounded potential, concave term, asymmetric reaction, critical groups, multiple solutions, Harnack inequalityFull text (file, 665,32 KB)
Keywords: indefinite and unbounded potential, Robin eigenvalue problem, sublinear perturbation, superlinear perturbation, maximum principle, positive solution, minimal positive solutionFull text (file, 759,32 KB)
Keywords: resonant problem, reduction method, regularity theory, indefinite and unbounded potential, local linkingFull text (file, 484,13 KB)
Keywords: indefinite and unbounded potential, critical groups, multiple solutions, nonlinear regularity, resonance, Robin boundary condition, strong comparison, truncationFull text (file, 673,65 KB)