{"title":"关于 <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\" id=\"d1e27\" altimg=\"si13.svg\" 假设反例的基点展开的说明","authors":"J. Blackman , S. Kristensen , M.J. Northey","doi":"10.1016/j.exmath.2024.125548","DOIUrl":null,"url":null,"abstract":"<div><p>In this paper, we investigate the base-<span><math><mi>p</mi></math></span> expansions of putative counterexamples to the <span><math><mi>p</mi></math></span>-adic Littlewood conjecture of de Mathan and Teulié. We show that if a counterexample exists, then so does a counterexample whose base-<span><math><mi>p</mi></math></span> expansion is uniformly recurrent. Furthermore, we show that if the base-<span><math><mi>p</mi></math></span> expansion of <span><math><mi>x</mi></math></span> is a morphic word <span><math><mrow><mi>τ</mi><mrow><mo>(</mo><msup><mrow><mi>φ</mi></mrow><mrow><mi>ω</mi></mrow></msup><mrow><mo>(</mo><mi>a</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> where <span><math><mrow><msup><mrow><mi>φ</mi></mrow><mrow><mi>ω</mi></mrow></msup><mrow><mo>(</mo><mi>a</mi><mo>)</mo></mrow></mrow></math></span> contains a subword of the form <span><math><mrow><mi>u</mi><mi>X</mi><mi>u</mi><mi>X</mi><mi>u</mi></mrow></math></span> with <span><math><mrow><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><mrow><mo>|</mo><msup><mrow><mi>φ</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>|</mo></mrow><mo>=</mo><mi>∞</mi></mrow></math></span>, then <span><math><mi>x</mi></math></span> satisfies the <span><math><mi>p</mi></math></span>-adic Littlewood conjecture. In the special case when <span><math><mrow><mi>p</mi><mo>=</mo><mn>2</mn></mrow></math></span>, we show that the conjecture holds for all pure morphic words.</p></div>","PeriodicalId":50458,"journal":{"name":"Expositiones Mathematicae","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S072308692400015X/pdfft?md5=9882f79608644e821115bc0ed83923d6&pid=1-s2.0-S072308692400015X-main.pdf","citationCount":"0","resultStr":"{\"title\":\"A note on the base-p expansions of putative counterexamples to the p-adic Littlewood conjecture\",\"authors\":\"J. Blackman , S. Kristensen , M.J. Northey\",\"doi\":\"10.1016/j.exmath.2024.125548\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In this paper, we investigate the base-<span><math><mi>p</mi></math></span> expansions of putative counterexamples to the <span><math><mi>p</mi></math></span>-adic Littlewood conjecture of de Mathan and Teulié. We show that if a counterexample exists, then so does a counterexample whose base-<span><math><mi>p</mi></math></span> expansion is uniformly recurrent. Furthermore, we show that if the base-<span><math><mi>p</mi></math></span> expansion of <span><math><mi>x</mi></math></span> is a morphic word <span><math><mrow><mi>τ</mi><mrow><mo>(</mo><msup><mrow><mi>φ</mi></mrow><mrow><mi>ω</mi></mrow></msup><mrow><mo>(</mo><mi>a</mi><mo>)</mo></mrow><mo>)</mo></mrow></mrow></math></span> where <span><math><mrow><msup><mrow><mi>φ</mi></mrow><mrow><mi>ω</mi></mrow></msup><mrow><mo>(</mo><mi>a</mi><mo>)</mo></mrow></mrow></math></span> contains a subword of the form <span><math><mrow><mi>u</mi><mi>X</mi><mi>u</mi><mi>X</mi><mi>u</mi></mrow></math></span> with <span><math><mrow><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><mrow><mo>|</mo><msup><mrow><mi>φ</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>u</mi><mo>)</mo></mrow><mo>|</mo></mrow><mo>=</mo><mi>∞</mi></mrow></math></span>, then <span><math><mi>x</mi></math></span> satisfies the <span><math><mi>p</mi></math></span>-adic Littlewood conjecture. In the special case when <span><math><mrow><mi>p</mi><mo>=</mo><mn>2</mn></mrow></math></span>, we show that the conjecture holds for all pure morphic words.</p></div>\",\"PeriodicalId\":50458,\"journal\":{\"name\":\"Expositiones Mathematicae\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2024-03-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S072308692400015X/pdfft?md5=9882f79608644e821115bc0ed83923d6&pid=1-s2.0-S072308692400015X-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Expositiones Mathematicae\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S072308692400015X\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Expositiones Mathematicae","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S072308692400015X","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
在本文中,我们研究了 de Mathan 和 Teulié 的 p-adic Littlewood 猜想的推定反例的基 p 展开。我们证明,如果一个反例存在,那么一个其基p展开是均匀递归的反例也存在。此外,我们还证明,如果 x 的基 p 扩展是一个形态词 τ(φω(a)),其中 φω(a) 包含一个形式为 uXuXu 的子词,且 limn→∞|φn(u)|=∞, 那么 x 满足 p-adic Littlewood 猜想。在 p=2 的特殊情况下,我们证明该猜想对所有纯形声字都成立。
A note on the base-p expansions of putative counterexamples to the p-adic Littlewood conjecture
In this paper, we investigate the base- expansions of putative counterexamples to the -adic Littlewood conjecture of de Mathan and Teulié. We show that if a counterexample exists, then so does a counterexample whose base- expansion is uniformly recurrent. Furthermore, we show that if the base- expansion of is a morphic word where contains a subword of the form with , then satisfies the -adic Littlewood conjecture. In the special case when , we show that the conjecture holds for all pure morphic words.
期刊介绍:
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