Games on Boolean algebras

Abstract

<p>The method of forcing is widely used in set theory to obtain&nbsp;various consistency proofs. Complete Boolean algebras play the main role&nbsp;in applications of forcing. Therefore it is useful to define games on Boolean&nbsp;algebras that characterize their properties important for the method. The&nbsp;most investigated game is Jech&rsquo;s distributivity game, such that the first&nbsp;player has the winning strategy iff the algebra is not (&omega;, 2)-distributive.&nbsp;We define another game characterizing the collapsing of the continuum to&nbsp;&omega;, prove several sufficient conditions for the second player to have a winning&nbsp;strategy, and obtain a Boolean algebra on which the game is undetermined.&nbsp;</p>

<p>Forsing je metod &scaron;iroko kori&scaron;ćen u teoriji skupova za dokaze konsistentnosti. Kompletne&nbsp; Bulove algebre igraju glavnu ulogu u primenama forsinga. Stoga je korisno definisati igre na Bulovim algebrama koje karakteri&scaron;u njihove osobine od značaja za taj metod. Najbolje proučena je Jehova igra, koja ima osobinu da prvi igrač ima pobedničku strategiju akko algebra nije (&omega;, 2)-distributivna. U tezi defini&scaron;emo jo&scaron; jednu igru, koja karakteri&scaron;e kolaps kontinuuma na &omega;, dokazujemo nekoliko dovoljnih uslova da bi drugi igra&scaron; imao pobedničku strategiju, i konstrui&scaron;emo Bulovu algebru na kojoj je igra neodređena.</p>