{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/multiple-timestep-reversible-n-body","title":"Multiple timestep reversible $N$-body integrators for close encounters in planetary systems","arxiv_id":"2401.07113","date":"2024-01-13","proceeding":null,"authors":["David M. Hernandez","Walter Dehnen"],"abstract":"We present new almost time-reversible integrators for solution of planetary systems consisting of \"planets\" and a dominant mass (\"star\"). The algorithms can be considered adaptive generalizations of the Wisdom--Holman method, in which all pairs of planets can be assigned timesteps. These timesteps, along with the global timestep, can be adapted time-reversibly, often at no appreciable additional compute cost, without sacrificing any of the long-term error benefits of the Wisdom--Holman method. The method can also be considered a simpler and more flexible version of the \\texttt{SYMBA} symplectic code. We perform tests on several challenging problems with close encounters and find the reversible algorithms are up to $2.6$ times faster than a code based on \\texttt{SYMBA}. The codes presented here are available on Github. We also find adapting a global timestep reversibly and discretely must be done in block-synchronized manner or similar.","url_abs":"https://arxiv.org/abs/2401.07113v2","url_pdf":"https://arxiv.org/pdf/2401.07113v2.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"multiple-timestep-reversible-n-body","repo_url":"https://github.com/dmhernan/reversible-stepping","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}