English

The compact support property for solutions to stochastic heat equations with stable noise

Probability 2025-08-12 v3

Abstract

We consider weak non-negative solutions to the stochastic partial differential equation tY(t,x)=ΔY(t,x)+Y(t,x)γL˙(t,x), \partial_t Y(t,x) = \Delta Y(t,x) + Y(t,x)^\gamma \dot{L}(t,x), for (t,x)R+×Rd(t,x) \in \mathbb{R}_+ \times \mathbb{R}^d, where γ>0\gamma > 0 and L˙\dot{L} is a one-sided stable noise of index α(1,2)\alpha \in (1,2). We prove that solutions with compactly supported initial data have compact support for all times if γ(2α,1)\gamma \in (2-\alpha, 1) for d=1d=1, and if γ[1/α,1)\gamma \in [1/\alpha,1) in dimensions d[2,2/(α1))Nd \in [2,2/(\alpha-1)) \cap \mathbb{N}. This complements known results on solutions to the equation with Gaussian noise. We also establish a stochastic integral formula for the density of a solution and associated moment bounds which hold in all dimensions for which solutions are defined.

Keywords

Cite

@article{arxiv.2212.04520,
  title  = {The compact support property for solutions to stochastic heat equations with stable noise},
  author = {Thomas Hughes},
  journal= {arXiv preprint arXiv:2212.04520},
  year   = {2025}
}

Comments

63 pages. Final version