Existence of nodal solutions for Dirac equations with singular nonlinearities

Abstract

We prove, by a shooting method, the existence of infinitely many solutions of the form $\psi (x^0,x)=e^{-i\Omega x^0}\chi (x)$ of the nonlinear Dirac equation {equation*} i\underset{μ=0}{\overset{3}{\sum}} γ^μ\partial_μψ- mψ- F(\barψψ)ψ= 0 {equation*} where $\Omega >m>0,$ $\chi$ is compactly supported and \[F(x) = \{{array}{ll} p|x|^{p-1} & \text{if} |x|>0 0 & \text{if} x=0 {array}.] with $p\in (0,1),$ under some restrictions on the parameters $p$ and $\Omega .$ We study also the behavior of the solutions as $p$ tends to zero to establish the link between these equations and the M.I.T. bag model ones.