Discovering the governing equations of dynamical systems is a central problem across many scientific disciplines. As experimental data become increasingly available, automated equation discovery methods offer a promising data-driven approach to accelerate scientific discovery. Among these methods, genetic programming (GP) has been widely adopted due to its flexibility and interpretability. However, GP-based approaches often suffer from inefficient exploration of the symbolic search space, leading to slow convergence and suboptimal solutions. To address these limitations, we propose LLM-ODE, a large language model-aided model discovery framework that guides symbolic evolution using patterns extracted from elite candidate equations. By leveraging the generative prior of large language models, LLM-ODE produces more informed search trajectories while preserving the exploratory strengths of evolutionary algorithms. Empirical results on 91 dynamical systems show that LLM-ODE variants consistently outperform classical GP methods in terms of search efficiency and Pareto-front quality. Overall, our results demonstrate that LLM-ODE improves both efficiency and accuracy over traditional GP-based discovery and offers greater scalability to higher-dimensional systems compared to linear and Transformer-only model discovery methods.
Figures & tables
Figure 1. Schematic overview of LLM-ODE. (1) Given trajectory data from an unknown dynamical system, the observations are decomposed into state variables. (2) A large language model acts as an evolutionary operator, guiding the evolution of symbolic equation populations toward higher-fitness candidates. (3) The final system of equations is selected from the Cartesian product of equation-level Pareto fronts.
Figure 3. System discovery rate as a function of search iterations across various NMSE thresholds λ . Overall, LLM-ODE methods achieve higher discovery rates across all iteration limits. LLM-ODE methods enjoy a faster convergence rate than PySR.
Figure 4. The number of points along the system Pareto front of GP-based methods during training. The error bars represent 95% confidence intervals across systems. LLM-ODE methods are more efficient at obtaining a diverse Pareto-front as compared to stochastic GP.
Figure 5. System pool sizes from which the system Pareto-front is computed.
Appendix figures & tables6 assets
Supplementary material from the paper’s appendix.
Appendix
Hyperparameter
Possible Values
Optimizer threshold
0.05, 0.1, 0.15
Optimizer alpha
0.025, 0.05, 0.075
Max iterations
20, 100
Polynomial degree
1,2,…,10
Basis functions
{ polynomials } { polynomials, sin, cos, exp} { polynomials, sin, cos, log, exp, sqrt, inverse }
Appendix
Table 2. Hyperparameter search space of SINDy.
Name
Train IV
Test IV
Equation
RC-circuit
x0=10.0
x0=3.54
x˙0=0.303−0.361x0
Population growth (naive)
x0=4.78
x0=0.87
x˙0=0.23x0
Population growth (carrying capacity)
x0=7.3
x0=21.0
x˙0=0.79x0(1−0.0135x0)
RC-circuit (nonlinear resistor)
x0=0.8
x0=0.02
x˙0=−0.5+1+1.65e−1.04x01
Velocity of a falling object
x0=0.5
x0=73.0
x˙0=9.81−0.00212x02
Autocatalysis
x0=0.13
x0=2.24
x˙0=−0.5x02+2.1x0
Appendix
Table 3. The governing equations and the initial values of one-dimensional ( D=1 ) dynamical systems.
Figure 6. The training trajectories of dynamical systems with D=1 state variables.
Figure 7. The training trajectories of dynamical systems with D=2 state variables.
Figure 8. The training trajectories of dynamical systems with D=3 state variables.
Figure 9. The training trajectories of dynamical systems with D=4 state variables.
Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, Rehovot, Israel · Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel · Mohamed bin Zayed University of Artificial Intelligence, Abu Dhabi, United Arab Emirates +2
Institute of Structural Engineering, ETH Zurich, Zurich, Switzerland · ETH AI Center, ETH Zurich, Zurich, Switzerland · Swiss Data Science Center, Zurich, Switzerland