Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 13 of 13

Full-Text Articles in Physics

Fourth Order Dispersion In Nonlinear Media, Georgios Tsolias Apr 2023

Fourth Order Dispersion In Nonlinear Media, Georgios Tsolias

Doctoral Dissertations

In recent years, there has been an explosion of interest in media bearing quartic
dispersion. After the experimental realization of so-called pure-quartic solitons, a
significant number of studies followed both for bright and for dark solitonic struc-
tures exploring the properties of not only quartic, but also setic, octic, decic etc.
dispersion, but also examining the competition between, e.g., quadratic and quartic
dispersion among others.
In the first chapter of this Thesis, we consider the interaction of solitary waves in
a model involving the well-known φ4 Klein-Gordon theory, bearing both Laplacian and biharmonic terms with different prefactors. As a …


On The Intermediate Long Wave Propagation For Internal Waves In The Presence Of Currents, Joseph Cullen, Rossen Ivanov Jan 2020

On The Intermediate Long Wave Propagation For Internal Waves In The Presence Of Currents, Joseph Cullen, Rossen Ivanov

Articles

A model for the wave motion of an internal wave in the presence of current in the case of intermediate long wave approximation is studied. The lower layer is considerably deeper, with a higher density than the upper layer. The flat surface approximation is assumed. The fluids are incompressible and inviscid. The model equations are obtained from the Hamiltonian formulation of the dynamics in the presence of a depth-varying current. It is shown that an appropriate scaling leads to the integrable Intermediate Long Wave Equation (ILWE). Two limits of the ILWE leading to the integrable Benjamin-Ono and KdV equations are …


Surface Waves Over Currents And Uneven Bottom, Alan Compelli, Rossen Ivanov, Calin I. Martin, Michail D. Todorov Jan 2019

Surface Waves Over Currents And Uneven Bottom, Alan Compelli, Rossen Ivanov, Calin I. Martin, Michail D. Todorov

Articles

The propagation of surface water waves interacting with a current and an uneven bottom is studied. Such a situation is typical for ocean waves where the winds generate currents in the top layer of the ocean. The role of the bottom topography is taken into account since it also influences the local wave and current patterns. Specific scaling of the variables is selected which leads to approximations of Boussinesq and KdV types. The arising KdV equation with variable coefficients, dependent on the bottom topography, is studied numerically when the initial condition is in the form of the one soliton solution …


Equatorial Wave–Current Interactions, Adrian Constantin, Rossen Ivanov Jan 2019

Equatorial Wave–Current Interactions, Adrian Constantin, Rossen Ivanov

Articles

We study the nonlinear equations of motion for equatorial wave–current interactions in the physically realistic setting of azimuthal two-dimensional inviscid flows with piecewise constant vorticity in a two-layer fluid with a flat bed and a free surface. We derive a Hamiltonian formulation for the nonlinear governing equations that is adequate for structure-preserving perturbations, at the linear and at the nonlinear level. Linear theory reveals some important features of the dynamics, highlighting differences between the short- and long-wave regimes. The fact that ocean energy is concentrated in the long-wave propagation modes motivates the pursuit of in-depth nonlinear analysis in the long-wave …


Nonlinear Waves And Solitons On Contours And Closed Surfaces, Andrei Ludu Dec 2011

Nonlinear Waves And Solitons On Contours And Closed Surfaces, Andrei Ludu

Andrei Ludu

No abstract provided.


Nonlinear Equations And Wavelets, Andrei Ludu Jan 2003

Nonlinear Equations And Wavelets, Andrei Ludu

Andrei Ludu

No abstract provided.


Nonlinear Phenomena In Nuclei: The Antisoliton Model For Fission, Andrei Ludu Jan 1999

Nonlinear Phenomena In Nuclei: The Antisoliton Model For Fission, Andrei Ludu

Andrei Ludu

No abstract provided.


Patterns On Liquid Surfaces: Cnoidal Waves, Compactons And Scaling, Andrei Ludu Jan 1998

Patterns On Liquid Surfaces: Cnoidal Waves, Compactons And Scaling, Andrei Ludu

Andrei Ludu

Localized patterns and nonlinear oscillation formation on the bounded free surface of an ideal incompressible liquid are analytically investigated. Cnoidal modes, solitons and compactons, as traveling non-axially symmetric shapes are discussed. A finite-difference differential generalized Korteweg-de Vries equation is shown to describe the three-dimensional motion of the fluid surface and the limit of long and shallow channels one re-obtains the well-known KdV equation. A tentative expansion formula for the representation of the general solution of a nonlinear equation, for given initial condition is introduced on a graphical-algebraic basis. The model is useful in multilayer fluid dynamics, cluster formation, and nuclear …


Nonlinear Liquid Drop Model. Cnoidal Waves, Andrei Ludu Dec 1996

Nonlinear Liquid Drop Model. Cnoidal Waves, Andrei Ludu

Andrei Ludu

No abstract provided.


Generalization Kdv Equation For Fluid Dynamics And Quantum Algebras, Andrei Ludu Dec 1995

Generalization Kdv Equation For Fluid Dynamics And Quantum Algebras, Andrei Ludu

Andrei Ludu

No abstract provided.


Alpha+28si Cluster Structure As Solitons On The Nuclear Surface, Andrei Ludu Jan 1995

Alpha+28si Cluster Structure As Solitons On The Nuclear Surface, Andrei Ludu

Andrei Ludu

No abstract provided.


Quasimolecular Resonances In Alpha+20ne Systems, Andrei Ludu Jan 1995

Quasimolecular Resonances In Alpha+20ne Systems, Andrei Ludu

Andrei Ludu

No abstract provided.


Cluster As Solitons On The Nuclear Surface, Andrei Ludu Jan 1991

Cluster As Solitons On The Nuclear Surface, Andrei Ludu

Andrei Ludu

No abstract provided.