This work investigates a coupled generalized Schrödinger-Boussinesq system with a $ p $-power nonlinearity. These equations appear in several physical applications. To begin, we present a complete classification of infinitesimal point symmetries for the system. Then, low-order local conservation laws are derived using the multiplier method, providing conserved quantities such as momentum, mass, and charge. By introducing a potential variable, we derive a Lagrangian formulation for the potential system and find nonlocal conservation laws via Noether's theorem. Finally, we explore travelling wave solutions by reducing the governing equations to a coupled autonomous system of ordinary differential equations. Several families of solutions are constructed, and their physical relevance is discussed.
Citation: Almudena P. Márquez, Tamara M. Garrido, Gaukhar Shaikhova, Rafael de la Rosa. Conservation laws and travelling wave solutions of a generalized NLS-Boussinesq system using symmetries[J]. Electronic Research Archive, 2026, 34(11): 8174-8202. doi: 10.3934/era.2026348
This work investigates a coupled generalized Schrödinger-Boussinesq system with a $ p $-power nonlinearity. These equations appear in several physical applications. To begin, we present a complete classification of infinitesimal point symmetries for the system. Then, low-order local conservation laws are derived using the multiplier method, providing conserved quantities such as momentum, mass, and charge. By introducing a potential variable, we derive a Lagrangian formulation for the potential system and find nonlocal conservation laws via Noether's theorem. Finally, we explore travelling wave solutions by reducing the governing equations to a coupled autonomous system of ordinary differential equations. Several families of solutions are constructed, and their physical relevance is discussed.
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