Bochner-Riesz means on a conical singular manifold
Qiuye Jia, Junyong Zhang, Jiqiang Zheng
TL;DR
This work determines the sharp L^p-boundedness threshold for Bochner-Riesz means on two-dimensional flat cones, showing that S_λ^δ(Δ_X) is bounded on L^p(X) for p ≠ 2 precisely when δ > δ_c(p,2) with δ_c(p,2) = max{0, 2|1/2 − 1/p| − 1/2}. The authors construct an explicit spectral-measure kernel for Δ_X, decompose the Bochner-Riesz kernel into geometric and diffractive components, and apply Stein–Hörmander oscillatory integral theory together with cone-specific Young-type estimates to handle diffraction at the cone vertex. A key reduction to σ > 1 via averaging over angular orbits enables the analysis to proceed uniformly, and the method extends to infinite sectors with Dirichlet/Neumann boundaries, resolving the wedge critical-exponent problem. The results provide a sharp, geometry-aware BR theory in the conical setting and lay groundwork for polygonal-domain problems by clarifying diffraction and long-time dynamics in two dimensions.
Abstract
We prove a sharp $L^p$-boundedness criterion for Bochner-Riesz multipliers on flat cones $X = (0,\infty) \times \mathbb{S}_σ^1$. The operator $S_λ^δ(Δ_X)$ is bounded on $L^p(X)$ for $1 \leq p \leq \infty$, $p \neq 2$, if and only if $δ> δ_c(p,2) = \max\left\{ 0, 2\left| 1/2 - 1/p \right| - 1/2 \right\}$. This result is also applicable to the infinite sector domain with Dirichlet or Neumann boundary, resolving the critical exponent problem in this wedge setting.
