トポロジー火曜セミナー
過去の記録 ~09/18|次回の予定|今後の予定 09/19~
開催情報 | 火曜日 17:00~18:30 数理科学研究科棟(駒場) 056号室 |
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担当者 | 河澄 響矢, 北山 貴裕, 逆井卓也 |
セミナーURL | http://park.itc.u-tokyo.ac.jp/MSF/topology/TuesdaySeminar/index.html |
2017年11月28日(火)
17:00-18:30 数理科学研究科棟(駒場) 056号室
Tea: Common Room 16:30-17:00
Sang-hyun Kim 氏 (Seoul National University)
Diffeomorphism Groups of One-Manifolds (ENGLISH)
Tea: Common Room 16:30-17:00
Sang-hyun Kim 氏 (Seoul National University)
Diffeomorphism Groups of One-Manifolds (ENGLISH)
[ 講演概要 ]
Let a>=2 be a real number and k = [a]. We denote by Diff^a(S^1) the group of C^k diffeomorphisms such that the k--th derivatives are Hölder--continuous of exponent (a - k). For each real number a>=2, we prove that there exists a finitely generated group G < Diff^a(S^1) such that G admits no injective homomorphisms into Diff^b(S^1) for any b>a. This is joint work with Thomas Koberda.
Let a>=2 be a real number and k = [a]. We denote by Diff^a(S^1) the group of C^k diffeomorphisms such that the k--th derivatives are Hölder--continuous of exponent (a - k). For each real number a>=2, we prove that there exists a finitely generated group G < Diff^a(S^1) such that G admits no injective homomorphisms into Diff^b(S^1) for any b>a. This is joint work with Thomas Koberda.