English

Perturbation from symmetry for semiconvex lower-order partial-wave nonlinear Dirac equations

Analysis of PDEs 2026-07-16 v1

Abstract

We study strongly indefinite nonlinear Dirac functionals in the lowest partial-wave channel with radial coefficients in R3\mathbb R^3. The symmetric model has the exact power nonlinearity F0(x,ψ)=b(x)ψp/pF_0(x,\psi)=b(|x|)|\psi|^p/p, where 2<p<32<p<3 and the radial profile bb is bounded, continuous, and uniformly positive. Compactness in this finite-angular-mode spinor channel and radial approximation-number estimates give quadratic growth of the symmetric minimax levels. For a non-even localized perturbation of order 1<τ<p/21<\tau<p/2, we impose a semiconvexity condition whose negative curvature is strictly smaller than the spectral gap. Together with the negative quadratic part and the convex exact-power core, this makes every negative spectral fiber uniformly strongly concave. Maximizing along that fiber reduces the problem to a C1C^1 path on the positive spectral space. The polynomial Chambers--Ghoussoub--Bolle deformation theorem then yields infinitely many high-energy critical points of the restricted partial-wave functional; under the channel-invariance hypothesis these are weak solutions of the full Dirac equation. Convex perturbing primitives are covered without a smallness restriction on their amplitude. The same reduction applies after an even Hermitian quadratic term is absorbed into a renormalized Dirac operator, provided the renormalized operator has a gap at zero and the remaining perturbation satisfies the corresponding semiconvexity bound.

Keywords

Cite

@article{arxiv.2607.14679,
  title  = {Perturbation from symmetry for semiconvex lower-order partial-wave nonlinear Dirac equations},
  author = {Francesco Paolo Maiale},
  journal= {arXiv preprint arXiv:2607.14679},
  year   = {2026}
}