On the Spectrum of Nonself-Adjoint Dirac Operators with Two-Point Boundary Conditions

Abstract: We consider the spectral problem for the Dirac operator with arbitrary two-point boundaryconditions and any square integrable potential. Necessary andsufficient conditions for an entire function to be the characteristic determinant of such an operatorare established. In the case of irregular boundary conditions, conditions are found under which aset of complex numbers is the spectrum of the problem under consideration. © Pleiades Publishing, Ltd. 2024.