{"paper":{"title":"Fast(er)PM and Moving Mesh: JAX-native Geometric Multigrid Methods","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["astro-ph.CO","astro-ph.GA"],"primary_cat":"astro-ph.IM","authors_text":"Benjamin Horowitz","submitted_at":"2026-07-13T01:07:44Z","abstract_excerpt":"Efficient, differentiable Poisson solvers are a key component of modern particle--mesh simulations and field-level inference pipelines. FFT-based solvers are extremely effective on fixed Cartesian meshes, but they impose global all-to-all communication and rely on symmetries that are lost in adaptive or non-Cartesian coordinates. In this work, we present a JAX-native geometric multigrid framework for particle--mesh gravity and argue that multigrid plays two complementary roles: on fixed meshes it can be a competitive, communication-avoiding alternative to FFTs, while on moving meshes it become"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.10983","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2607.10983/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}