翻訳と辞書
Words near each other
・ Łozienica
・ Łozina
・ Łozinka
・ Łoziska
・ Łozowe, Podlaskie Voivodeship
・ Łozowo
・ Łozowo-Kolonia
・ Łozy
・ Łozy, Lubusz Voivodeship
・ Łozy, Masovian Voivodeship
・ Łozy, Warmian-Masurian Voivodeship
・ Łońsko
・ Łoś, Masovian Voivodeship
・ Łośnica
・ Łośno
Łoś–Tarski preservation theorem
・ Łoźnica, West Pomeranian Voivodeship
・ Łoźnik
・ Łoża
・ Łuba Druga
・ Łubcze
・ Łubia
・ Łubiana
・ Łubiana railway station
・ Łubiane
・ Łubianka, Augustów County
・ Łubianka, Greater Poland Voivodeship
・ Łubianka, Kuyavian-Pomeranian Voivodeship
・ Łubianka, Masovian Voivodeship
・ Łubianka, Pomeranian Voivodeship


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Łoś–Tarski preservation theorem : ウィキペディア英語版
Łoś–Tarski preservation theorem
The Łoś–Tarski theorem is a theorem in model theory, a branch of mathematics, that states that the set of formulas preserved under taking substructures is exactly the set of ''universal'' formulas (Hodges 1997).
== Statement ==

Let T be a theory in a first-order language L and
\Phi(\bar) a set of formulas of L.
(The set of sequence of variables \bar need not be
finite.) Then the following are equivalent:
# If A and B are models of T, A \subseteq B, \bar is a sequence of elements of A and B \models \bigwedge \Phi(\bar), then A \models \bigwedge \Phi(\bar).
(\Phi is preserved in substructures for models of T)
# \Phi is equivalent modulo T to a set \Psi(\bar) of \forall_1 formulas of L.
A formula is \forall_1 if and only if it is of the form \forall \bar () where \psi(\bar) is quantifier-free.
Note that this property fails for finite models.

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「Łoś–Tarski preservation theorem」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.