Analytical Structures and Conservation Laws of the (2+1)-Dimensional Cubic Klein-Gordon Equation
The (2+1) cubic Klein-Gordon equation is used in a wide range of disciplines, including river floods, tsunami wave propagation, breakwater construction and management, dam-break scenarios, coastal engineering, and many phenomena in physical oceanography. The goal of this study is to establish wave solutions using the extended rational sine-cosine and sinh-cosh techniques (ERSC). The provided approaches enable the construction of a variety of novel solutions with distinct forms. The solutions are closely tied to physical characteristics, with particular waveform features that appear under certain conditions. Furthermore, the new conservation theorem is applied to systematically deduce conservation laws from Lie-point symmetry. Graphical representations in two- and three-dimensional formats are plotted to demonstrate the propagation of selected exact solutions that include a variety of parameter values.