activity
20202026
collaborators

7 papers

math.AP2026

Compressible steady water waves

Abba Ramadan, Samuel Walsh

In this paper, we consider the existence of small- and large-amplitude compressible water waves. These are solutions of the two-dimensional free boundary isentropic Euler equations…

math.AP2026

Minimizers for the Cahn-Hilliard energy functional with the Flory-Huggins potential under strong anchoring conditions

Shibin Dai, Abba Ramadan, Natasha Sharma

In this paper, we theoretically and numerically study the minimizers for the Cahn-Hilliard energy with the Flory-Huggins potential under the strong anchoring condition, i.e., the D…

math.AP2026

Curve Lengthening Bifurcations in Modally Filtered Nonlinear Schrödinger Systems

Keith Promislow, Abba Ramadan

Extensions of the parametric nonlinear Schrödinger equations (PNLS) for phase-sensitive optical resonance are developed that preserve the curve lengthening bifurcation seen in the…

math.AP2023

Curvature and Chaos in the Defocusing Parameteric Nonlinear Schrodinger System

Keith Promislow, Abba Ramadan

The parametric nonlinear Schrodinger equation models a variety of parametrically forced and damped dispersive waves. For the defocusing regime, we derive a normal velocity for the…

math.AP2023

On the stability of solitary waves in the NLS system of the third-harmonic generation

Abba Ramadan, Atanas G. Stefanov

We consider the NLS system of the third-harmonic generation, which was introduced by Sammut. Our interest is in solitary wave solutions and their stability properties. The recent w…

math.AP2021

On the stability of the compacton waves for the degenerate KdV and NLS models

Sevdzhan Hakkaev, Abba Ramadan, Atanas G. Stefanov

In this paper, we consider the degenerate semi-linear Schrödinger and Korteweg-deVries equations in one spatial dimension. We construct special solutions of the two models, namely…

math.AP2020

On the standing waves of the Schroedinger equation with concentrated nonlinearity

Abba Ramadan, Atanas G. Stefanov

We study the concentrated NLS on , with power non-linearities, driven by the fractional Laplacian, . We construct the solitary waves explicitl…