The Massless Dirac Equation in Three Dimensions: Dispersive estimates and zero energy obstructions

Autor: Green, William R., Lane, Connor, Lyons, Benjamin, Ravishankar, Shyam, Shaw, Aden
Rok vydání: 2024
Předmět:
Zdroj: Journal of Differential Equations, Volume 416, Part 1, 2025, Pages 449-490
Druh dokumentu: Working Paper
DOI: 10.1016/j.jde.2024.10.005
Popis: We investigate dispersive estimates for the massless three dimensional Dirac equation with a potential. In particular, we show that the Dirac evolution satisfies a $\langle t\rangle^{-1}$ decay rate as an operator from $L^1$ to $L^\infty$ regardless of the existence of zero energy eigenfunctions. We also show this decay rate may be improved to $\langle t\rangle ^{-1-\gamma}$ for any $0\leq \gamma < 1/2$ at the cost of spatial weights. This estimate, along with the $L^2$ conservation law allows one to deduce a family of Strichartz estimates in the case of a threshold eigenvalue. We classify the structure of threshold obstructions as being composed of zero energy eigenfunctions. Finally, we show the Dirac evolution is bounded for all time with minimal requirements on the decay of the potential and smoothness of initial data.
Comment: Updated to reflect referee comments. Published in the Journal of Differential Equations
Databáze: arXiv