Functional differential operators with involution and Dirac operators with periodic boundary conditions (Q403912)

The paper summarizes results concerning eigenvalues and eigenfunctions of the functional operators with involution \[ L^{\pm}y=y'(x)\pm q(x)y(1-x),\quad y(0)=y(1), \quad x\in[0,1] \] by means of the corresponding Dirac operator. The Riesz projectors of the Dirac operator are also investigated.