Dynamic Kuramoto-Hodge Operators for PDEs on Complex Geometries and Topologies
Organizations: Tsinghua University · Beijing University of Chemical Technology
Abstract
Learning PDE operators on complex domains requires capturing interactions among fields on vertices, edges, and faces, alongside global responses shaped by topology. Existing neural operators accommodate irregular geometries but often overlook these distinct field supports or their condition-dependent coupling. We introduce the Dynamic Kuramoto--Hodge Operator (DKHO), which combines topology-constrained interactions with learned coordination. DKHO encodes conditions on their native cochain supports, evolves Kuramoto-inspired relation states through the boundary and coboundary operators that compose the Dirac operator, and decodes non-harmonic and harmonic responses in orthogonal Hodge subspaces. Topology thus determines where information can flow, while learned dynamics adapts how it is exchanged to each PDE instance. Across porous-medium Darcy flow, torus transport--diffusion, and cavity magnetostatics, DKHO-large reduces prediction error by approximately 61% on average over leading baselines, while DKHO-small remains competitive using only 11.5--24.3% as many parameters. These results suggest that coupling topological structure with adaptive dynamics provides an effective inductive bias for accurate and parameter-efficient PDE operator learning on complex geometries and topologies.
Figures & tables
| Method | Params (K) | MSE | RelL2 | Div Fid | Curl MSE | Vort Fid | Enst Fid | Energy Fid | IoU |
|---|---|---|---|---|---|---|---|---|---|
| GNO | 231.5 | 2.30e-3 | 1.1030 | 0.5673 | 1.5409 | 0.4970 | 0.2387 | 0.3714 | 0.1400 |
| FNO | 227.4 | 4.59e-5 | 0.1189 | 0.9887 | 1.93e-2 | 0.9098 | 0.8721 | 0.9053 | 0.7242 |
| MGN | 246.6 | 1.66e-4 | 0.2532 | 0.9590 | 6.10e-2 | 0.8008 | 0.6970 | 0.8752 | 0.5555 |
| DeepONet | 238.9 | 1.07e-5 | 0.0814 | 0.9967 | 1.07e-2 | 0.9361 | 0.8356 | 0.9661 | 0.7984 |
| Geo-FNO | 252.7 | 4.23e-5 | 0.1152 | 0.9895 | 1.61e-2 | 0.9236 | 0.8870 | 0.9091 | 0.7234 |
| HSD | 265.4 | 7.20e-6 | 0.0547 | 0.9981 | 7.03e-3 | 0.9675 | 0.9513 | 0.9681 | 0.8268 |
Appendix figures & tables21 assets
Supplementary material from the paper’s appendix.
Appendix
| Symbol | Definition |
|---|---|
| Geometry and cochains | |
| , | Oriented Riemannian domain and its oriented simplicial discretization. |
| , | Set of oriented -simplices and its cardinality. |
| , | Smooth -forms and discrete -cochains with channels. |
| , | Physical output cochain and known PDE conditions. |
| Differential operators and topology | |
| System | Physical forms | Governing relations |
|---|---|---|
| Darcy flow | Potential ; line flux | , |
| Heat diffusion | Temperature ; heat flux | , |
| Surface transport | Density ; transport | , |
| Magnetostatics (3D) | Field ; flux | , , |
| Maxwell system (3D) | ; | , |
| Reaction–diffusion | Species ; diffusive flux | , |
| State | Value space | Role in a layer |
|---|---|---|
| Content | Condition-dependent representation from which the requested field is decoded. | |
| Relation | Accumulated coordination state, coupled through incidence and read through sine/cosine maps. |
| PDE family | Conditions, support assignment, and output observables |
|---|---|
| Poisson / Darcy | Source samples, boundary traces, and material coefficients; vertex values, oriented edge differences, and face-integrated source descriptors. Outputs: potential , line flux , and derived circulation . |
| Heat / diffusion | Initial temperature, diffusivity, and boundary data; vertex values with optional fixed diffusion filters of the initial state. Outputs: temperature and line-integrated heat flux . |
| Surface transport | Initial concentration, tangent velocity, and diffusivity; vertex concentration, oriented edge velocity, and initial mass summaries. Outputs: terminal concentration , edge transport , and face mass . |
| Incompressible flow | Body force, velocity traces, and pressure gauge; encode vector components or their oriented line integrals with boundary frames. Outputs: pressure and velocity one-cochains; normal flux uses degree . |
| Linear elasticity | Displacement, traction, and stiffness data; attach vector/tensor components to vertices or cells and integrate boundary loads. Outputs: vector displacement and vector-valued traction integrals on degree . |
| Electrostatics / magnetostatics | Sources, material data, and boundary indicators; input-derived source moments and support geometry. Outputs: scalar potential or, in 3D, surface-flux two-cochains, optionally reconstructed as node vectors. |
| Operation | Work | Storage |
|---|---|---|
| Incidence and local geometry (offline) | ||
| Spectral bases (offline) | Eigensolver-dependent | Number of stored coefficients |
| Conditioning maps, one evaluation | ||
| Relation feedback, one substep | ||
| Content update, one layer | ||
| Output projection and synthesis | basis |
| Task and | Train | Val. | Test | |
|---|---|---|---|---|
| Darcy: | 4,000 | 500 | 500 | |
| Torus: | 2,040 | 360 | 600 | |
| Cavity: | 2,040 | 360 | 600 |
| Target | S params | L params | Batch | Epochs (S/L) | Selected (S/L) |
|---|---|---|---|---|---|
| Darcy | 64,121 | 242,657 | 16 | 200/200 | 187/199 |
| Darcy | 64,475 | 243,363 | 16 | 200/200 | 200/200 |
| Darcy | 64,121 | 242,657 | 16 | 300/300 | 300/294 |
| Torus | 63,546 | 241,506 | 16 | 300/300 | 292/289 |
| Torus | 64,347 | 243,107 | 16 | 300/300 | 297/298 |
| Torus | 64,314 | 243,042 | 16 | 300/300 | 299/294 |
| Method | Darcy; torus | Torus | Cavity |
|---|---|---|---|
| GNO | Hidden 120, projection 68; 3 layers, radius 0.15 | Hidden 120, projection 68; 3 layers, radius 0.15 | Hidden 84, projection 96; 5 layers, radius 0.20 |
| FNO | Width 21; 3 layers; modes | Width 20; 3 layers; modes | Width 21; 2 layers; modes |
| MGN | Hidden 72; 8 steps | Hidden 72; 8 steps | Hidden 64; 10 steps |
| DeepONet | Branch ; trunk ; 64 bases | Branch ; trunk ; 64 bases | Branch/trunk ; 74 bases |
| Geo-FNO | Width 18; 4 layers; modes | Width 8; 4 layers; modes | Width 12; 2 layers; modes |
| HSD | Residual width 12; 6 layers; modes | Residual width 12; 6 layers; modes | Residual width 14; 4 layers; modes |
| Task | Decay | Batch | Epochs | Stopping rule |
|---|---|---|---|---|
| Darcy | 16 | 200 | Full budget; select minimum validation error. | |
| Torus | 32 | 200 | Full budget; select minimum validation error. | |
| Torus | 16 | 200 | Full budget; select minimum validation error. | |
| Cavity | 32 | 200 | Full budget; select minimum validation error. |
| Task | Native inputs | Added descriptors |
|---|---|---|
| Darcy | Coefficients, boundary traces, and support geometry | Degree-wise Laplacian bases (16 modes), heat descriptors, and global condition summaries |
| Torus | , tangent velocity, geometry, and fixed inter-degree transfers | Torus Fourier coordinates, low-order summaries of , and Laplacian, heat, mass, and energy descriptors |
| Cavity | Source/magnetization channels and shell geometry | Boundary/cavity indicators, Laplacian bases, source heat responses, and global source moments |
| Method | Native (N) | Matched (F) | ||||
| GNO | 5.673e-4 | 9.834e-5 | 2.793e-5 | 1.625e-5 | 1.893e-5 | 2.938e-6 |
| FNO | 0.0063 | 0.0071 | 0.0022 | 0.0063 | 0.0071 | 0.0022 |
| MGN | 0.0076 | 4.724e-4 | 1.420e-4 | 5.984e-5 | 1.067e-5 | 3.029e-6 |
| DeepONet | 2.367e-4 | 0.0067 | 0.0023 | 1.406e-4 | 0.0069 | 0.0023 |
| Geo-FNO | 0.0154 | 0.0066 | 0.0021 | 0.0147 | 0.0069 | 0.0021 |
| Method | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| RelL2 | Grad | RelL2 | CD | Curl | RelL2 | CB | IoU | ||
| DKHO-small | 0.0042 | 0.9985 | 0.9889 | 0.0264 | 0.9990 | 0.9986 | 0.0392 | 0.9996 | 0.9848 |
| DKHO-large | 0.0035 | 0.9989 | 0.9922 | 0.0155 | 0.9997 | 0.9996 | 0.0244 | 0.9998 | 0.9905 |
| GNO | 0.0058 | 0.9957 | 0.9916 | 0.0511 | 0.9968 | 0.9964 | 0.0371 | 0.9996 | 0.9861 |
| FNO | 0.1113 | 0.6837 | 0.8018 | 0.9736 | 0.6019 | 0.5066 | 0.9948 | 0.5460 | 0.6062 |
| MGN | 0.0112 | 0.9936 | 0.9823 | 0.0390 | 0.9984 | 0.9982 | 0.0379 | 0.9996 | 0.9835 |
| Method | Native (N) | Matched (F) | ||||
| GNO | 0.0417 | 3.604e-4 | 1.255e-7 | 0.0153 | 3.995e-4 | 1.209e-7 |
| FNO | 0.0171 | 0.0013 | 4.796e-7 | 0.1170 | 0.0013 | 4.791e-7 |
| MGN | 0.0224 | 7.284e-5 | 4.842e-8 | 0.0120 | 7.779e-5 | 5.672e-8 |
| DeepONet | 0.0513 | 0.0013 | 5.160e-7 | 0.0811 | 0.0013 | 4.090e-7 |
| Geo-FNO | 0.0343 | 0.0014 | 5.669e-7 | 0.0172 | 0.0014 | 5.519e-7 |
| Method | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| RelL2 | Grad | IoU | RelL2 | CD | Curl | RelL2 | CB | IoU | |
| DKHO-small | 0.1428 | 0.8440 | 0.8776 | 0.1310 | 0.9615 | 0.8026 | 0.1142 | 0.9666 | 0.9117 |
| DKHO-large | 0.1413 | 0.8472 | 0.8798 | 0.1262 | 0.9633 | 0.8187 | 0.1007 | 0.9737 | 0.9267 |
| GNO | 0.2075 | 0.8024 | 0.8097 | 0.3923 | 0.8111 | 0.5585 | 0.2122 | 0.9016 | 0.8258 |
| FNO | 0.5917 | 0.6326 | 0.5052 | 0.6687 | 0.6929 | 0.5116 | 0.4172 | 0.6174 | 0.5990 |
| MGN | 0.1790 | 0.8280 | 0.8423 | 0.1660 | 0.9338 | 0.7038 | 0.1252 | 0.9398 | 0.8872 |
| Method | Native (N) | Matched (F) |
| GNO | 2.30e-3 | 1.374e-6 |
| FNO | 4.587e-5 | 8.932e-6 |
| MGN | 1.658e-4 | 1.331e-6 |
| DeepONet | 1.069e-5 | 5.792e-6 |
| Geo-FNO | 4.229e-5 | 9.891e-6 |
| HSD | 7.198e-6 | 1.522e-4 |
| Method | Native (N) | Matched (F) | ||||
|---|---|---|---|---|---|---|
| RelL2 | Div | IoU | RelL2 | Div | IoU | |
| DKHO-small | – | – | – | 0.0179 | 0.9996 | 0.9650 |
| DKHO-large | – | – | – | 0.0140 | 0.9997 | 0.9724 |
| GNO | 1.1030 | 0.5673 | 0.1400 | 0.0190 | 0.9996 | 0.9585 |
| FNO | 0.1189 | 0.9887 | 0.7242 | 0.0619 | 0.9979 | 0.7948 |
| MGN | 0.2532 | 0.9590 | 0.5555 | 0.0219 | 0.9997 | 0.9328 |
| Target | Baseline | Params (K) | Ratio | RelL2 | ||
|---|---|---|---|---|---|---|
| S | B | S | B | |||
| Darcy | DeepONet | 64.1 | 559.1 | 11.5% | 0.0042 | 0.0218 |
| Darcy | GNO | 64.5 | 285.9 | 22.6% | 0.0264 | 0.1129 |
| Darcy | GNO | 64.1 | 285.9 | 22.4% | 0.0392 | 0.1104 |
| Torus | FNO | 63.5 | 309.1 | 20.5% | 0.1428 | 0.2440 |
| Torus | MGN | 64.3 | 303.2 | 21.2% | 0.1310 | 0.1581 |
| Target | Full | No Dirac | No phase | No harmonic |
|---|---|---|---|---|
| Darcy | 0.0042 | 0.0144 | 0.0062 | — |
| Darcy | 0.0264 | 0.1124 | 0.0407 | 0.0310 |
| Darcy | 0.0392 | 0.4698 | 0.0484 | — |
| Torus | 0.1428 | 0.2877 | 0.1518 | 0.1465 |
| Torus | 0.1310 | 0.3104 | 0.1469 | 0.1355 |
| Torus | 0.1142 | 0.4072 | 0.1229 | 0.1688 |
| Metric | Darcy | Torus | Cavity |
|---|---|---|---|
| Instances | 500 | 600 | 600 |
| Support | |||
| Spearman | |||
| Dice | |||
| Lift | |||
| Enrichment |
| Task | Case | Dice | Lift | Enr. | RelL2 | |
|---|---|---|---|---|---|---|
| Darcy | 1 | 0.524 | 2.18 | 1.47 | 0.0197 | |
| 2 | 0.512 | 2.13 | 1.46 | 0.0195 | ||
| 3 | 0.506 | 2.11 | 1.46 | 0.0164 | ||
| Torus | 1 | 0.700 | 3.50 | 2.98 | 0.1166 | |
| 2 | 0.663 | 3.32 | 1.98 | 0.0752 | ||
| 3 | 0.653 | 3.26 | 2.04 | 0.0874 |