RT journal article T1 Lie symmetries and exact solutions for a fourth-order nonlinear diffusion equation A1 Márquez Lozano, Almudena del Pilar A1 Garrido Letrán, Tamara María A1 Recio Rodríguez, Elena A1 Rosa Silva, Rafael de la A2 Matemáticas K1 diffusion equations K1 exact solutions K1 Lie group analysis K1 symmetry reductions AB In this paper, we consider a fourth-order nonlinear diffusion partial differentialequation, depending on two arbitrary functions. First, we perform an analysisof the symmetry reductions for this parabolic partial differential equation byapplying the Lie symmetry method. The invariance property of a partial differentialequation under a Lie group of transformations yields the infinitesimalgenerators. By using this invariance condition, we present a complete classificationof the Lie point symmetries for the different forms of the functions thatthe partial differential equation involves. Afterwards, the optimal systems ofone-dimensional subalgebras for each maximal Lie algebra are determined, bycomputing previously the commutation relations, with the Lie bracket operator,and the adjoint representation. Next, the reductions to ordinary differentialequations are derived from the optimal systems of one-dimensional subalgebras.Furthermore, we study travelling wave reductions depending on the form of thetwo arbitrary functions of the original equation. Some travelling wave solutionsare obtained, such as solitons, kinks and periodic waves. PB WILEY SN 0170-4214 YR 2022 FD 2022-06 LK http://hdl.handle.net/10498/26982 UL http://hdl.handle.net/10498/26982 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 21-sep-2026