The Fractal Lie Derivative: Theory and Applications
Alireza Khalili Golmankhaneh, Elham Hashemzadeh, Carlo Cattani, Donal O'Regan, Palle E. T. Jørgensen
TL;DR
The paper develops a Lie-theoretic framework for fractal calculus to analyze symmetries and conservation laws in fractal dynamical systems. By introducing $d_{F}^{\alpha}$, $D_{F}^{\alpha}$, the $k$-fractal jet space, and fractal prolongations, it extends Noether's theorem to fractal Lagrangian mechanics, deriving conserved currents $J$ with $D_{F}^{\alpha} J = 0$ and fractal Euler–Lagrange equations. It then builds a comprehensive differential-geometry toolkit for fractal manifolds—covering fractal differential forms, wedge products, the exterior derivative, Lie derivatives, and jet-space methods—and applies symmetry analysis to nonlinear and linear fractal differential equations, yielding explicit infinitesimals and generators for representative cases, including time-translation, scaling, and oscillatory symmetries. The work provides a rigorous, extensible framework for modeling and solving fractal-dynamics problems, with potential applications in physics and complex fractal media.
Abstract
This paper presents a new Lie theoretic approach to fractal calculus, which in turn yields such new results as a Fractal Noether's Theorem, a setting for fractal differential forms, for vector fields, and Lie derivatives, as well as k-fractal jet space, and algorithms for k-th fractal prolongation. The symmetries of the fractal nonlinear \(n\)-th \(α\)-order differential equation are examined, followed by a discussion of the symmetries of the fractal linear \(n\)-th \(α\)-order differential equation. Additionally, the symmetries of the fractal linear first \(α\)-order differential equation are derived. Several examples are provided to illustrate and highlight the details of these concepts.
