2021/09/14 by Li, Zhi-Qiang, Tian, Shou-Fu, Yang, Jin-Jie
#Analysis of PDEs (math.AP) #Exactly Solvable and Integrable Systems (nlin.SI) #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph)
paper · doi:10.48550/arxiv.2109.06384
In this work, we investigate the Cauchy problem of the Wadati-Konno-Ichikawa (WKI) equation with finite density initial data. Employing the ∂-generalization of Deift-Zhou nonlinear steepest descent method, we derive the long time asymptotic behavior of the solution q(x,t) in space-time soliton region. Based on the resulting asymptotic behavior, the asymptotic approximation of the WKI equation is characterized with the soliton term confirmed by N(I)-soliton on discrete spectrum and the t-(1)/(2) leading order term on continuous spectrum with residual error up to O(t-(3)/(4)). Our results also confirm the soliton resolution conjecture for the WKI equation with finite density initial data.