{"title":"概率伽罗瓦理论:平方判别情况","authors":"Lior Bary-Soroker, Or Ben-Porath, Vlad Matei","doi":"10.1112/blms.13049","DOIUrl":null,"url":null,"abstract":"<p>The paper studies the probability for a Galois group of a random polynomial to be <span></span><math>\n <semantics>\n <msub>\n <mi>A</mi>\n <mi>n</mi>\n </msub>\n <annotation>$A_n$</annotation>\n </semantics></math>. We focus on the so-called large box model, where we choose the coefficients of the polynomial independently and uniformly from <span></span><math>\n <semantics>\n <mrow>\n <mo>{</mo>\n <mo>−</mo>\n <mi>L</mi>\n <mo>,</mo>\n <mtext>…</mtext>\n <mo>,</mo>\n <mi>L</mi>\n <mo>}</mo>\n </mrow>\n <annotation>$\\lbrace -L,\\ldots , L\\rbrace$</annotation>\n </semantics></math>. The state-of-the-art upper bound is <span></span><math>\n <semantics>\n <mrow>\n <mi>O</mi>\n <mo>(</mo>\n <msup>\n <mi>L</mi>\n <mrow>\n <mo>−</mo>\n <mn>1</mn>\n </mrow>\n </msup>\n <mo>)</mo>\n </mrow>\n <annotation>$O(L^{-1})$</annotation>\n </semantics></math>, due to Bhargava. We conjecture a much stronger upper bound <span></span><math>\n <semantics>\n <msup>\n <mi>L</mi>\n <mrow>\n <mo>−</mo>\n <mi>n</mi>\n <mo>/</mo>\n <mn>2</mn>\n <mo>+</mo>\n <mi>ε</mi>\n </mrow>\n </msup>\n <annotation>$L^{-n/2 +\\epsilon }$</annotation>\n </semantics></math>, and that this bound is essentially sharp. We prove strong lower bounds both on this probability and on the related probability of the discriminant being a square.</p>","PeriodicalId":55298,"journal":{"name":"Bulletin of the London Mathematical Society","volume":"56 6","pages":"2162-2177"},"PeriodicalIF":0.8000,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1112/blms.13049","citationCount":"0","resultStr":"{\"title\":\"Probabilistic Galois Theory: The square discriminant case\",\"authors\":\"Lior Bary-Soroker, Or Ben-Porath, Vlad Matei\",\"doi\":\"10.1112/blms.13049\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The paper studies the probability for a Galois group of a random polynomial to be <span></span><math>\\n <semantics>\\n <msub>\\n <mi>A</mi>\\n <mi>n</mi>\\n </msub>\\n <annotation>$A_n$</annotation>\\n </semantics></math>. We focus on the so-called large box model, where we choose the coefficients of the polynomial independently and uniformly from <span></span><math>\\n <semantics>\\n <mrow>\\n <mo>{</mo>\\n <mo>−</mo>\\n <mi>L</mi>\\n <mo>,</mo>\\n <mtext>…</mtext>\\n <mo>,</mo>\\n <mi>L</mi>\\n <mo>}</mo>\\n </mrow>\\n <annotation>$\\\\lbrace -L,\\\\ldots , L\\\\rbrace$</annotation>\\n </semantics></math>. The state-of-the-art upper bound is <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>O</mi>\\n <mo>(</mo>\\n <msup>\\n <mi>L</mi>\\n <mrow>\\n <mo>−</mo>\\n <mn>1</mn>\\n </mrow>\\n </msup>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$O(L^{-1})$</annotation>\\n </semantics></math>, due to Bhargava. We conjecture a much stronger upper bound <span></span><math>\\n <semantics>\\n <msup>\\n <mi>L</mi>\\n <mrow>\\n <mo>−</mo>\\n <mi>n</mi>\\n <mo>/</mo>\\n <mn>2</mn>\\n <mo>+</mo>\\n <mi>ε</mi>\\n </mrow>\\n </msup>\\n <annotation>$L^{-n/2 +\\\\epsilon }$</annotation>\\n </semantics></math>, and that this bound is essentially sharp. We prove strong lower bounds both on this probability and on the related probability of the discriminant being a square.</p>\",\"PeriodicalId\":55298,\"journal\":{\"name\":\"Bulletin of the London Mathematical Society\",\"volume\":\"56 6\",\"pages\":\"2162-2177\"},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2024-04-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1112/blms.13049\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Bulletin of the London Mathematical Society\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1112/blms.13049\",\"RegionNum\":3,\"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":"Bulletin of the London Mathematical Society","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1112/blms.13049","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Probabilistic Galois Theory: The square discriminant case
The paper studies the probability for a Galois group of a random polynomial to be . We focus on the so-called large box model, where we choose the coefficients of the polynomial independently and uniformly from . The state-of-the-art upper bound is , due to Bhargava. We conjecture a much stronger upper bound , and that this bound is essentially sharp. We prove strong lower bounds both on this probability and on the related probability of the discriminant being a square.