Recovering closed-form PDE solutions from standard NNs via symbolic distillation

Establish whether symbolic distillation with SymTorch can recover the analytic solution u(x,t) = exp(−π^2 α t) sin(π x) of the 1-D heat equation from a standard neural network trained on the same sparse dataset, given that the method succeeds for a Physics-Informed Neural Network under identical conditions but failed for the standard neural network in the reported experiments.

Background

The study compares a standard neural network and a Physics-Informed Neural Network (PINN) trained on ten data points from the 1-D heat equation. Using SymTorch, the authors successfully distill the correct closed-form solution from the PINN.

However, they explicitly report being unable to distill the same solution from the standard neural network, leaving open whether such recovery is possible for non-physics-regularized models trained on the same data.

References

From the trained PINN, we were able to distill the correct form of the 1-D heat equation solution as given in \cref{eqn:1d_heat_solution} with the constants correct to 2 decimal points. However, we were unable to do this for the regular NN.

SymTorch: A Framework for Symbolic Distillation of Deep Neural Networks  (2602.21307 - Tan et al., 24 Feb 2026) in Appendix: Extracting PDE Solutions from a PINN Details → Results