{ "id": "2404.19233", "version": "v1", "published": "2024-04-30T03:30:31.000Z", "updated": "2024-04-30T03:30:31.000Z", "title": "Avoiding short progressions in Euclidean Ramsey theory", "authors": [ "Gabriel Currier", "Kenneth Moore", "Chi Hoi Yip" ], "comment": "12 pages", "categories": [ "math.CO" ], "abstract": "We provide a general framework to construct colorings avoiding short monochromatic arithmetic progressions in Euclidean Ramsey theory. Specifically, if $\\ell_m$ denotes $m$ collinear points with consecutive points of distance one apart, we say that $\\mathbb{E}^n \\not \\to (\\ell_r,\\ell_s)$ if there is a red/blue coloring of $n$-dimensional Euclidean space that avoids red congruent copies of $\\ell_r$ and blue congruent copies of $\\ell_s$. We show that $\\mathbb{E}^n \\not \\to (\\ell_3, \\ell_{20})$, improving the best-known result $\\mathbb{E}^n \\not \\to (\\ell_3, \\ell_{1177})$ by F\\\"uhrer and T\\'oth, and also establish $\\mathbb{E}^n \\not \\to (\\ell_4, \\ell_{18})$ and $\\mathbb{E}^n \\not \\to (\\ell_5, \\ell_{10})$ in the spirit of the classical result $\\mathbb{E}^n \\not \\to (\\ell_6, \\ell_{6})$ due to Erd{\\H{o}}s et. al. We also show a number of similar $3$-coloring results, as well as $\\mathbb{E}^n \\not \\to (\\ell_3, \\alpha\\ell_{6889})$, where $\\alpha$ is an arbitrary positive real number. This final result answers a question of F\\\"uhrer and T\\'oth in the positive.", "revisions": [ { "version": "v1", "updated": "2024-04-30T03:30:31.000Z" } ], "analyses": { "subjects": [ "05D10", "52C10", "11B25" ], "keywords": [ "euclidean ramsey theory", "avoiding short progressions", "colorings avoiding short monochromatic arithmetic", "construct colorings avoiding short monochromatic", "avoiding short monochromatic arithmetic progressions" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }