High-Order Noether’s Transformation and New Densities for BBM Equation via Contact Symmetries

Subject Areas : International Journal of Mathematical Modelling & Computations

Mehdi Jafari ^{1 *} , Mojtaba Farazi ²

1 - Payame Noor University (PNU), Department of Mathematics, P.O. Box 19395-4697, Tehran, Iran.
2 - Payame Noor University (PNU), Department of Mathematics, P.O. Box 19395-4697, Tehran, Iran.

Received: 2023-10-01 Accepted : 2023-12-25 Published : 2024-11-15

Keywords: BBM equation, Generalized symmetries, Multiplier method, Contact symmetries, Conservation laws.,

Abstract :

Noether's first theorem shows how symmetry groups of one-parameter transformations lead to the generation of conservation laws for the Euler-Lagrange equations. She states in her second theorem that there is a relationship between Euler's basic equation and Lagrange's basic equation. This one-to-one correspondence leads to a type of symmetry called generalized symmetry. According to these materials, in this paper, we want to obtain these types of symmetries for the Benjamin-Bona-Mahony (BBM) equation and show that each symmetry is connected to a specific conservation law. For this purpose, we obtain the symmetries of this equation using the Lie symmetry method, and then using the adjoint operator, we provide a classification on the group invariant solutions of this equation. Then, by applying Noether's method, we obtain a new conservation law for each symmetry.

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