LieDiscover finds complex mathematical symmetries in data automatically

LieDiscover: Adaptive Symbolic Library Construction for Explicit Open-form Symmetry Discovery

Symbolic ComputationMachine Learning

Summary

Finding hidden patterns called symmetries in data helps scientists understand natural laws. Existing methods struggle to identify complicated symmetries that involve advanced math formulas. The authors propose LieDiscover, a new approach that builds and improves a library of mathematical expressions step-by-step using a learning method. This lets LieDiscover find very complex hidden symmetries that other methods miss and helps solve equations better.

What this means in practice

Authors

Xinxin Li, Jianming Ma, Xingyu Cui, Da Li, Juan Zhang, Junping Yin

Abstract

Discovering underlying symmetries from data has emerged as a crucial challenge in scientific discovery. Existing data-driven methods for symmetry discovery fail to determine the exact number and mathematical form of unknown infinitesimal generators. Recent explicit methods represent generators using a predefined function library and identify them through algebraic optimization, but they often struggle to capture complex symmetries involving high-order polynomials or transcendental functions. To address this limitation, we formulate symmetry discovery as a joint optimization problem over the function library and coefficients. We propose a novel framework that leverages an encoder-decoder architecture to dynamically generate symbolic expressions and expand the library. This generation process is optimized via reinforcement learning, which accelerates the exploration of the symbolic search space through step-wise rewards. Experiments demonstrate that LieDiscover can successfully uncover open-form infinitesimal generators involving high-order polynomials or transcendental functions, which remain intractable for existing methods. The discovered symmetries also improve performance in downstream PDE solving and discovery tasks.