Forced oscillation of a damped BBM equation posed on whole line in low regularity spaces
Chun Ho Lau, Taige Wang
TL;DR
This work studies forced damped BBM dynamics on $\mathbb{R}$ in low-regularity spaces $H^\ell$, $\ell\in[0,1)$. It employs the $I$-method with the operator $I_N$ to lift to an $H^1$-based framework and proves local and global well-posedness, along with existence and stability of time-periodic solutions under time-periodic forcing. Key contributions include bilinear/trilinear estimates and a fixed-point scheme that establish mild solutions in $Y^\ell_{\tau,T}$, the construction of time-periodic states, and exponential stability results that persist globally under small forcing. The results extend damped BBM/KdV-type dynamics to rough data, providing a rigorous handle on long-time behavior and asymptotic periodicity in low-regularity settings.
Abstract
In this manuscript, we would established in low regularity spaces $H^\ell, \ell\in [0,1)$, the existence and stability results of time-periodic solution of 1D Cauchy problem of forced damped Benjamin-Bona-Mahony equation (BBM). We use estimates from I-energy method to derive needed estimates in $H^\ell$ for the linearized problem, then convection term will be treated as perturbation of linear problem such that original Cauchy problem is solved.
