{"title":"无限世界和主谋数字","authors":"Joel David Hamkins","doi":"10.1002/malq.202200049","DOIUrl":null,"url":null,"abstract":"<p>I consider the natural infinitary variations of the games Wordle and Mastermind, as well as their game-theoretic variations Absurdle and Madstermind, considering these games with infinitely long words and infinite color sequences and allowing transfinite game play. For each game, a secret codeword is hidden, which the codebreaker attempts to discover by making a series of guesses and receiving feedback as to their accuracy. In Wordle with words of any size from a finite alphabet of <i>n</i> letters, including infinite words or even uncountable words, the codebreaker can nevertheless always win in <i>n</i> steps. Meanwhile, the <i>mastermind number</i> <math>\n <semantics>\n <mi>m</mi>\n <annotation>$\\mathbbm {m}$</annotation>\n </semantics></math>, defined as the smallest winning set of guesses in infinite Mastermind for sequences of length ω over a countable set of colors without duplication, is uncountable, but the exact value turns out to be independent of <math>\n <semantics>\n <mi>ZFC</mi>\n <annotation>$\\mathsf {ZFC}$</annotation>\n </semantics></math>, for it is provably equal to the eventually different number <math>\n <semantics>\n <mrow>\n <mi>d</mi>\n <mo>(</mo>\n <msup>\n <mo>≠</mo>\n <mo>∗</mo>\n </msup>\n <mo>)</mo>\n </mrow>\n <annotation>$\\mathfrak {d}({\\ne ^*})$</annotation>\n </semantics></math>, which is the same as the covering number of the meager ideal <math>\n <semantics>\n <mrow>\n <mrow>\n <mtext>cov</mtext>\n </mrow>\n <mo>(</mo>\n <mi>M</mi>\n <mo>)</mo>\n </mrow>\n <annotation>$\\operatorname{\\mbox{cov}}(\\mathcal {M})$</annotation>\n </semantics></math>. I thus place all the various mastermind numbers, defined for the natural variations of the game, into the hierarchy of cardinal characteristics of the continuum.</p>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/malq.202200049","citationCount":"2","resultStr":"{\"title\":\"Infinite Wordle and the mastermind numbers\",\"authors\":\"Joel David Hamkins\",\"doi\":\"10.1002/malq.202200049\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>I consider the natural infinitary variations of the games Wordle and Mastermind, as well as their game-theoretic variations Absurdle and Madstermind, considering these games with infinitely long words and infinite color sequences and allowing transfinite game play. For each game, a secret codeword is hidden, which the codebreaker attempts to discover by making a series of guesses and receiving feedback as to their accuracy. In Wordle with words of any size from a finite alphabet of <i>n</i> letters, including infinite words or even uncountable words, the codebreaker can nevertheless always win in <i>n</i> steps. Meanwhile, the <i>mastermind number</i> <math>\\n <semantics>\\n <mi>m</mi>\\n <annotation>$\\\\mathbbm {m}$</annotation>\\n </semantics></math>, defined as the smallest winning set of guesses in infinite Mastermind for sequences of length ω over a countable set of colors without duplication, is uncountable, but the exact value turns out to be independent of <math>\\n <semantics>\\n <mi>ZFC</mi>\\n <annotation>$\\\\mathsf {ZFC}$</annotation>\\n </semantics></math>, for it is provably equal to the eventually different number <math>\\n <semantics>\\n <mrow>\\n <mi>d</mi>\\n <mo>(</mo>\\n <msup>\\n <mo>≠</mo>\\n <mo>∗</mo>\\n </msup>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\mathfrak {d}({\\\\ne ^*})$</annotation>\\n </semantics></math>, which is the same as the covering number of the meager ideal <math>\\n <semantics>\\n <mrow>\\n <mrow>\\n <mtext>cov</mtext>\\n </mrow>\\n <mo>(</mo>\\n <mi>M</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\operatorname{\\\\mbox{cov}}(\\\\mathcal {M})$</annotation>\\n </semantics></math>. I thus place all the various mastermind numbers, defined for the natural variations of the game, into the hierarchy of cardinal characteristics of the continuum.</p>\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2023-09-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1002/malq.202200049\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/malq.202200049\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/malq.202200049","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
I consider the natural infinitary variations of the games Wordle and Mastermind, as well as their game-theoretic variations Absurdle and Madstermind, considering these games with infinitely long words and infinite color sequences and allowing transfinite game play. For each game, a secret codeword is hidden, which the codebreaker attempts to discover by making a series of guesses and receiving feedback as to their accuracy. In Wordle with words of any size from a finite alphabet of n letters, including infinite words or even uncountable words, the codebreaker can nevertheless always win in n steps. Meanwhile, the mastermind number , defined as the smallest winning set of guesses in infinite Mastermind for sequences of length ω over a countable set of colors without duplication, is uncountable, but the exact value turns out to be independent of , for it is provably equal to the eventually different number , which is the same as the covering number of the meager ideal . I thus place all the various mastermind numbers, defined for the natural variations of the game, into the hierarchy of cardinal characteristics of the continuum.