Document Type
Article
Publication Title
Annals of PDE
Publication Date
2026
Keywords
damped waves, singular damping, backward uniqueness, Schrödinger observability
Abstract
We study energy decay rates for the damped wave equation with unbounded damping, without the geometric control condition. Our main decay result is sharp polynomial energy decay for polynomially controlled singular damping on the torus. We also prove that for normally Lp-damping on compact manifolds, the Schrödinger observability gives p-dependent polynomial decay, and finite time extinction cannot occur. We show that polynomially controlled singular damping on the circle gives exponential decay.
Funding Source
PBK is partially supported by NSF grant DMS-2530465. RPTW is partially supported by NSF grant DMS-2054424. This article was published Open Access thanks to a transformative agreement between Milner Library and Springer Nature.
Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.
DOI
10.1007/s40818-025-00230-2
Recommended Citation
Kleinhenz, P., Wang, R.P.T. Sharp Polynomial Decay for Polynomially Singular Damping on the Torus. Ann. PDE 12, 6 (2026). https://doi.org/10.1007/s40818-025-00230-2
Comments
First published in Annals of PDE (2026): https://doi.org/10.1007/s40818-025-00230-2. Supplemental information freely available on the publisher's site.