[過去ﾛｸﾞ] 現代数学の系譜11 ガロア理論を読む13 [転載禁止]©2ch.net (654ﾚｽ)
上下前次1-新
抽出解除 ﾚｽ栞
このｽﾚｯﾄﾞは過去ﾛｸﾞ倉庫に格納されています｡
次ｽﾚ検索 歴削→次ｽﾚ 栞削→次ｽﾚ 過去ﾛｸﾞﾒﾆｭｰ
ﾘﾛｰﾄﾞ規制です｡10分ほどで解除するので､他のﾌﾞﾗｳｻﾞへ避難してください｡
220(4): 現代数学の系譜11 ガロア理論を読む 2015/04/29(水)10:01 ID:6XYDeD+q(11/25) AAS
>>119
外部ﾘﾝｸ[pdf]:www.jmilne.org
1.^ J. S. Milne, Fields and Galois Theory, pp.100-101.（上記に同じ）
P113
REMARK 9.18 What are the automorphisms of C?
There are only two continuous automorphisms (cf. Exercise A-8 and solution).
If we assume Zorn’s lemma, then it is easy to construct many: choose any transcendence basis A for C over Q, and choose any permutation α of A;
省6
223(1): 現代数学の系譜11 ガロア理論を読む 2015/04/29(水)12:02 ID:6XYDeD+q(13/25) AAS
>>220
>What are the automorphisms of C?
>There are only two continuous automorphisms (cf. Exercise A-8 and solution).
>If we assume Zorn’s lemma, then it is easy to construct many: choose any transcendence basis A for C over Q, and choose any permutation α of A;
下記だね
外部ﾘﾝｸ:ja.wikipedia.org
複素数 C の場合は、R を R の中へ移す非自明な自己同型は複素共役ただ一つである。
省4
227(1): 現代数学の系譜11 ガロア理論を読む 2015/04/29(水)14:32 ID:6XYDeD+q(14/25) AAS
>>220
>Without Zorn’s lemma, there are only two, because the noncontinuous automorphisms are nonmeasurable,*1 and it is known that the Zorn’s lemma is required to construct nonmeasurable functions.*2
> 1) A fairly elementary theorem of G. Mackey says that measurable homomorphisms of Lie groups are continuous
> (see Theorem B.3, p. 198 of Zimmer, Robert J., Ergodic theory and semisimple groups. Birkh¨auser,1984.)
> 2)“We show that the existence of a non-Lebesgue measurable set cannot be proved in Zermelo-Frankel set theory (ZF) if use of the axiom of choice is disallowed...” R. Solovay, Ann. of Math., 92 (1970), 1?56.
１）there are only two：ここは上記の自明と、非自明な自己同型 複素共役の二つ
because the noncontinuous automorphisms are nonmeasurable,*1：”measurable homomorphisms of Lie groups are continuous”の対偶だね。Lie groupsなんだ・・
省6
233: 現代数学の系譜11 ガロア理論を読む 2015/04/29(水)15:19 ID:6XYDeD+q(20/25) AAS
R. Solovay, Ann. of Math., 92 (1970), 1?56 >>220
In 1970, Solovay constructed Solovay's model, >>228
Robert M. Solovay
外部ﾘﾝｸ:en.wikipedia.org
Robert Martin Solovay (born December 15, 1938) is an American mathematician specializing in set theory.
Solovay earned his Ph.D. from the University of Chicago in 1964 under the direction of Saunders Mac Lane, with a dissertation on A Functorial Form of the Differentiable Riemann?Roch theorem.
Solovay has spent his career at the University of California at Berkeley, where his Ph.D. students include W. Hugh Woodin and Matthew Foreman.
省1
241(7): 現代数学の系譜11 ガロア理論を読む 2015/04/29(水)17:32 ID:6XYDeD+q(24/25) AAS
>>238-240
なるほど、それは、考えとしてはすばらしいね
絶対大事なことだよ
が、一つ問題は、「関数f(x)のグラフを座標平面上で描いて考える」が、環同型写像f：R→Rのとき常に成り立つと言えるかどうかだね
もっと言えば、>>220
"If we assume Zorn’s lemma, then it is easy to construct many: choose any transcendence basis A for C over Q, and choose any permutation α of A;"とあるだろ？
こういう例を、環同型写像f：R→Rの場合にどうやって排除するか
上下前次1-新書関写板覧索設栞歴
ｽﾚ情報 赤ﾚｽ抽出 画像ﾚｽ抽出 歴の未読ｽﾚ AAｻﾑﾈｲﾙ
ぬこの手 ぬこTOP 0.020s