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In model theory, a branch of mathematical logic, the Hrushovski construction generalizes the Fraïssé limit by working with a notion of ''strong substructure'' rather than . It can be thought of as a kind of "model-theoretic forcing", where a (usually) stable structure is created, called the ''generic''. The specifics of determine various properties of the generic, with its geometric properties being of particular interest. It was initially used by Ehud Hrushovski to generate a stable structure with an "exotic" geometry, thereby refuting Zil'ber's Conjecture. == Three conjectures == The initial applications of the Hrushovski construction refuted two conjectures and answered a third question in the negative. Specifically, we have: * Lachlan's Conjecture Any stable -categorical theory is totally transcendental. * Zil'ber's Conjecture Any uncountably categorical theory is either locally modular or interprets an algebraically closed field. * Cherlin's Question Is there a maximal (with respect to expansions) strongly minimal set? 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Hrushovski construction」の詳細全文を読む スポンサード リンク
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