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arXiv · 2611.08421

Data-driven discovery of intrinsic Lie point symmetries of differential equation systems

Ilker Gurcan·Kadir Ustun·Ramazan Gokberk Cinbis
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Abstract

Discovering continuous symmetries directly from differential-equation data can reveal geometric structure for model reduction and scientific machine learning without symbolic determining equations or a closed-form representation of the governing system. We formulate intrinsic Lie point-symmetry discovery as an operator-theoretic problem on sampled jet-space data. Admissible generators are identified from a sampled determining operator and separated from redundant, solution-dependent, and geometrically trivial directions. The framework combines prolongation, sequential subspace restrictions, and a fixed nonlinear dictionary linear in trainable coefficients. A rank-stabilization preflight test diagnoses systems whose represented intrinsic symmetry algebra does not stabilize under dictionary refinement. On a controlled differential-equation benchmark with an analytically known 11-dimensional represented intrinsic symmetry algebra, the method recovers the complete represented generator set, reproduces its Lie-bracket structure to numerical precision, and approximates a known generator beyond the training domain. Here we show that explicit intrinsic continuous-symmetry generators can be recovered from data obtained from exact or approximate differential systems.

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Ilker Gurcan, Kadir Ustun, Ramazan Gokberk Cinbis. 2026-11-05. Data-driven discovery of intrinsic Lie point symmetries of differential equation systems. https://arxiv.org/abs/2611.08421

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