All public logs

Combined display of all available logs of Apeirology Wiki. You can narrow down the view by selecting a log type, the username (case-sensitive), or the affected page (also case-sensitive).

• 15:06, 9 September 2023 RhubarbJayde talk contribs created page Ordinal definable (Created page with "Ordinal definability is a concept which is key in certain aspects of inner model theory. We say a set \(x\) is ordinal-definable iff there is an ordinal \(\beta\) and a collection \(\alpha_1, \alpha_2, \cdots, \alpha_n\) of ordinals so that \(x \in V_\beta\) and there is a first-order formula \(\varphi\) such that, for all \(y \in V_\beta\), \(y = x\) iff \(V_\beta \models \varphi(y, \alpha_1, \alpha_2, \cdots, \alpha_n)\). In other words, it is definable at some ini...") Tag: Visual edit