Publication: Linear Non-Autonomous Heat Flow in $$L_0^1({{\mathbb {R}}}^{d})$$ and Applications to Elliptic Equations in $${{\mathbb {R}}}^{d}$$
Loading...
Official URL
Full text at PDC
Publication Date
2022-10-11
Authors
Robinson, James C.
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Springer
Citations
Exportar
Abstract
We study solutions of the equation ut−Δu+λu=f, for initial data that is ‘large at infinity’ as treated in our previous papers on the unforced heat equation. When f=0 we characterise those (u0,λ) for which solutions converge to 0 as t→∞, as not every λ>0 is able to achieve that for all initial data. When f≠0 we give conditions to guarantee that the solution is given by the usual ‘variation of constants formula’ u(t)=e−λtS(t)u0+∫t0e−λ(t−s)S(t−s)f(s)ds, where S(⋅) is the heat semigroup. We use these results to treat the elliptic problem −Δu+λu=f when f is allowed to be ‘large at infinity’, giving conditions under which a solution exists that is given by convolution with the usual Green’s function for the problem. Many of our results are sharp when u0,f≥0.
Description
CRUE-CSIC (Acuerdos Transformativos 2022)