In earlier works, we have shown the uniform decay of the local energy of thedamped wave equation in exterior domain when the damper is spatially localizednear captive rays. In order to have uniform decay of the total energy, thedamper has also to act at space infinity. In this work, we establish uniformdecay of both the local and global energies. The rates of decay turns out to bethe same as those for the heat equation, which shows that an effective damperat space infinity strengthens the parabolic structure in the equation.
展开▼
