Optimal Decay Rates to Conservation Laws with Diffusion-Type Terms of Regularity-gain and Regularity-loss
arXiv:1104.1271
Abstract
We consider the Cauchy problem on nonlinear scalar conservation laws with a diffusion-type source term related to an index over the whole space for any spatial dimension . Here, the diffusion-type source term behaves as the usual diffusion term over the low frequency domain while it admits on the high frequency part a feature of regularity-gain and regularity-loss for and , respectively. For all , we not only obtain the - time-decay estimates on the linear solution semigroup but also establish the global existence and optimal time-decay rates of small-amplitude classical solutions to the nonlinear Cauchy problem. In the case of regularity-loss, the time-weighted energy method is introduced to overcome the weakly dissipative property of the equation. Moreover, the large-time behavior of solutions asymptotically tending to the heat diffusion waves is also studied. The current results have general applications to several concrete models arising from physics.