Raport Badawczy = Research Report ; RB/93/2007
Instytut Badań Systemowych. Polska Akademia Nauk ; Systems Research Institute. Polish Academy of Sciences
30 pages ; 21 cm ; Bibliography p. 29-30
We derive global in time a priori bounds on higher-level energy norms of strong solutions to a semilinear wave equation: in particular, we prove that despite the influence of a nonlinear source, the evolution of a smooth initial state is globally bounded in the strong topology ∼ H2 × H1. And the bound is uniform with respect to the corresponding norm of the initial data. It is known that an m-accretive semigroup generator monotonically propagates smoothness of the initial condition; however, this result does not hold in general for Lipschitz perturbations of monotone systems where higher order Sobolev norms of the solution may blowup asymptotically as t → ∞. Due to nonlinearity of the system, the only a priori global-in-time bound that follows from classical methods is that on finite energy: ∼ H1 × L2. We show that under some correlation between growth rates of the damping and the source, the norms of topological order above the finite energy level remain globally bounded. Moreover, we also establish this result when damping exhibits sublinear or superlinear growth at the origin, or at infinity, which has immediate applications to asymptotic estimates on the decay rates of the finite energy. The approach presented in the paper is not specific to the wave equation, and can be extended to other hyperbolic systems: e.g. plate, Maxwell, and Schrödinger equations.
Raport Badawczy = Research Report
Creative Commons Attribution BY 4.0 license
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Systems Research Institute of the Polish Academy of Sciences
Library of Systems Research Institute PAS
Oct 19, 2021
Oct 19, 2021
32
https://rcin.org.pl/ibsys/publication/255050
Szulc, Katarzyna Żochowski, Antoni Lasiecka, Irena
Szulc, Katarzyna Żochowski, Antoni Lasiecka, Irena