Discrete Heat Equation with irregular thermal conductivity and tempered distributional data

Abstract

In this paper, we consider a semi-classical version of the nonhomogeneous heat equation with singular time-dependent coefficients on the lattice $\hslash {\mathbb{Z}}^n$. We establish the well-posedeness of such Cauchy equations in the classical sense when regular coefficients are considered, and analyse how the notion of very weak solution adapts in such equations when distributional coefficients are regarded. We prove the well-posedness of both the classical and the very weak solution in the weighted spaces ${\ell }_s^2(\hslash {\mathbb{Z}}^n)$, $s\in \mathbb{R}$, which is enough to prove the well-posedness in the space of tempered distributions ${\mathcal{S}}^{\prime }(\hslash {\mathbb{Z}}^n)$. Notably, when $s=0$, we show that for $\hslash \to 0$, the classical (resp. very weak) solution of the heat equation in the Euclidean setting ${\mathbb{R}}^n$ is recaptured by the classical (resp. very weak) solution of it in the semi-classical setting $\hslash {\mathbb{Z}}^n$.

References in corpus (4)

• Very weak solutions of wave equation for Landau Hamiltonian with irregular electromagnetic field
• Hyperbolic second order equations with non-regular time dependent coefficients
• Wave equation for operators with discrete spectrum and irregular propagation speed
• The heat equation with strongly singular potentials