$L^p$-estimates for the wave equation with critical magnetic potential on conical manifolds

Abstract: In this paper, we consider a class of conical singular spaces $\Sigma=(0,\infty)r\times Y$ equipped with the metric $g=\mathrm{d}r^2+r^2h$, where the cross section $Y$ is a compact $(n-1)$-dimensional closed Riemannian manifold $(Y,h)$ without boundary. In this context, we aim to show that the sine wave propagator $\sin\left(t\sqrt{\mathcal{L}{\mathbf{A}}}\right)/\sqrt{\mathcal{L}{\mathbf{A}}}$ is bounded in $L^{p}(\Sigma)$, where $\mathcal{L}{\mathbf{A}}$ is a magnetic Schr\"odinger operator with a scaling-critical magnetic potential on metric cone $\Sigma$. Our main result is the generalization of the result in \cite{L}. The novel ingredient is the construction of Hadamard parametrix for $\cos\left(t\sqrt{\mathcal{L}_{\bf A}}\right)$ on $\Sigma$.