{"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}
引用次数: 2
Abstract
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.