2004/12/11 by Alberto Cialdea, Cialdea, Alberto, Vladimir Maz’ya +2 · 3 citations
Engineering · Mathematics · #47B44 (Secondary) #47D03 (Primary) 47D06 #Analysis of PDEs (math.AP) #Differential Equations and Boundary Problems #FOS: Mathematics #Spectral Theory in Mathematical Physics #Stability and Controllability of Differential Equations #math.AP #msc:47B44 #msc:47D03 #msc:47D06
paper · pdf · doi:10.48550/arxiv.math/0412225
37 pages, LaTeX, no figures
arxiv created 2004/12/11 · openalex publication_date 2004/12/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We prove that the algebraic condition |p-2| |< \mathscr Im\mathscr Aξ,ξ>| ≤ 2 √(p-1) < \mathscr Re\mathscr Aξ,ξ> (for any ξ∈ℝn) is necessary and sufficient for the Lp-dissipativity of the Dirichlet problem for the differential operator ∇t(\mathscr A∇), where \mathscr A is a matrix whose entries are complex measures and whose imaginary part is symmetric. This result is new even for smooth coefficients, when it implies a criterion for the Lp-contractivity of the corresponding semigroup. We consider also the operator ∇t(\mathscr A∇)+\bf b∇ +a, where the coefficients are smooth and \mathscr Im\mathscr A may be not symmetric. We show that the previous algebraic condition is necessary and sufficient for the Lp-quasi-dissipativity of this operator. The same condition is necessary and sufficient for the Lp-quasi-contractivity of the corresponding semigroup. We give a necessary and sufficient condition for the Lp-dissipativity in ℝn of the operator ∇t(\mathscr A∇)+\bf b∇ +a with constant coefficients.