Boundary behavior and optimal pointwise Hölder exponent of the total local time of $(1+β)$-stable super-Brownian motion

Abstract

Let $L^x$ be the total local time of one-dimensional super-Brownian motion with $(1+β)$-stable branching mechanism, $0<β<1$. We prove that $\{x\in\mathbb R:L^x>0\}$ is almost surely a bounded open interval $(\mathsf L,\mathsf R)$ and that \[ h_L(\mathsf L)=h_L(\mathsf R)=1+\frac{2}β \] almost surely, where $h_L$ denotes the pointwise Hölder exponent. Thus the pointwise $γ$-Hölder condition holds at both endpoints for every $γ<1+2/β$ and fails for every $γ>1+2/β$. The same conclusions hold under the canonical excursion measure.