Papers › Symmetric Basis Convolutions for Learning Lagrangian Fluid Mechanics

Symmetric Basis Convolutions for Learning Lagrangian Fluid Mechanics

25 Mar 2024arXiv:2403.16680archive 2025-07-28

Rene Winchenbach, Nils Thuerey

Learning physical simulations has been an essential and central aspect of many recent research efforts in machine learning, particularly for Navier-Stokes-based fluid mechanics. Classic numerical solvers have traditionally been computationally expensive and challenging to use in inverse problems, whereas Neural solvers aim to address both concerns through machine learning. We propose a general formulation for continuous convolutions using separable basis functions as a superset of existing methods and evaluate a large set of basis functions in the context of (a) a compressible 1D SPH simulation, (b) a weakly compressible 2D SPH simulation, and (c) an incompressible 2D SPH Simulation. We demonstrate that even and odd symmetries included in the basis functions are key aspects of stability and accuracy. Our broad evaluation shows that Fourier-based continuous convolutions outperform all other architectures regarding accuracy and generalization. Finally, using these Fourier-based networks, we show that prior inductive biases, such as window functions, are no longer necessary. An implementation of our approach, as well as complete datasets and solver implementations, is available at https://github.com/tum-pbs/SFBC.

PaperPDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2403.16680")

Code

Syntology Ran 12 of 19 code samples harvested from 1 repository linked to this paper; 7 have no recorded run. Of those that ran: 2 ran · our draft was wrong; 2 ran · fixture could not drive it; 8 ran with no contract checked.

By repository: official repository: 19 samples from 1 repository, 12 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

tum-pbs/sfbc officialmentioned in papermentioned on GitHubpytorchMIT report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

19 samples harvested; 12 ran; 0 honoured the contract we drafted; 7 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

2ran · our draft was wrong
2ran · fixture could not drive it
8ran
7unverified

Licence: 0 of the 19 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from tum-pbs/sfbc. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

buildMLP tum-pbs/sfbc/src/BasisConvolution/convLayerv2.py official repository ran · our draft was wrong MIT (permissive) · 01098f7fb5af8aca · report
buildMLPwActivation tum-pbs/sfbc/src/BasisConvolution/convNetv2.py official repository ran · fixture could not drive it MIT (permissive) · 73dad65c3366c0d6 · report
buildMLPwActivation tum-pbs/SFBC/src/BasisConvolution/convNetv2.py official repository ran MIT (permissive) · 4b944e56a24334ac · report
buildMLPwDict tum-pbs/sfbc/src/BasisConvolution/convNetv2.py official repository ran · our draft was wrong MIT (permissive) · e12dd94211676bc2 · report
buildMLPwDict tum-pbs/SFBC/src/BasisConvolution/convNetv2.py official repository ran MIT (permissive) · 48f466cb501e970c · report
generateParticles tum-pbs/SFBC/eval/performanceMeasurement.py official repository ran fingerprinted MIT (permissive) · 416ab51cf7beeb85 · report
getActivationLayer tum-pbs/sfbc/src/BasisConvolution/convNetv2.py official repository ran · fixture could not drive it MIT (permissive) · 3233434225504ec6 · report
getActivationLayer tum-pbs/SFBC/src/BasisConvolution/convNetv2.py official repository ran MIT (permissive) · fa19f4aff56b0e77 · report
interpolant tum-pbs/SFBC/eval/noise/perlin.py official repository ran MIT (permissive) · bab05c8bf9da0a70 · report
pdf tum-pbs/SFBC/datasets/generate_test_case_I.py official repository ran fingerprinted MIT (permissive) · d607897d6ca51fd7 · report
perlinNoise2D tum-pbs/SFBC/eval/noise/perlin.py official repository ran MIT (permissive) · 948426e08e8e096a · report
perlinNoise3D tum-pbs/SFBC/eval/noise/perlin.py official repository ran MIT (permissive) · 12f727770539acfe · report
generateSimplex tum-pbs/SFBC/eval/noise/generator.py official repository unverified MIT (permissive) · 0acf386a76e369ea · report
get_analytical_jacobian tum-pbs/SFBC/eval/gradcheck.py official repository unverified MIT (permissive) · e43814b5b0bb50d9 · report
get_numerical_jacobian tum-pbs/SFBC/eval/gradcheck.py official repository unverified MIT (permissive) · 64a48db8e27bbcf2 · report
get_numerical_jacobian_wrt_specific_input tum-pbs/SFBC/eval/gradcheck.py official repository unverified MIT (permissive) · 301b0e6586be3e19 · report
initializeWeights2D tum-pbs/sfbc/src/BasisConvolution/convLayerv2.py official repository unverified MIT (permissive) · 004b54582bca041e · report
neighSearch tum-pbs/SFBC/eval/performanceMeasurement.py official repository unverified MIT (permissive) · 99edd179c77682a7 · report
supportFromVolume tum-pbs/SFBC/eval/performanceMeasurement.py official repository unverified MIT (permissive) · a59b6f0cab7277f5 · report

Tasks

Physical Simulations

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Methods

SET

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections