Existence of global solutions to a quasilinear Schrödinger equation with general nonlinear optimal control conditions (Q2126593)

The authors consider the global solutions of a fourth-order equation, involving the second power of the Laplacian and odd power nonlinearities. Solutions can be regarded as standing waves to a corresponding fourth-order Schrodinger equation, of relevance in Mathematical Physics. In the discussion, the authors use an interesting modified version of the classical maximum principle approach. The editors-in-chief of the journal have retracted this article, for the motivations, see the retraction note [ibid. 2021, Paper No. 24, 1 p. (2021; Zbl 07509868)].