Lie群論・表現論セミナー
過去の記録 ~10/14|次回の予定|今後の予定 10/15~
開催情報 | 火曜日 16:30~18:00 数理科学研究科棟(駒場) 126号室 |
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担当者 | 小林俊行 |
セミナーURL | https://www.ms.u-tokyo.ac.jp/~toshi/seminar/ut-seminar.html |
2010年02月02日(火)
16:30-18:00 数理科学研究科棟(駒場) 056号室
トポロジー火曜セミナーとの合同で行います。いつもと場所が違います。
Fanny Kassel 氏 (Orsay)
Deformation of compact quotients of homogeneous spaces
トポロジー火曜セミナーとの合同で行います。いつもと場所が違います。
Fanny Kassel 氏 (Orsay)
Deformation of compact quotients of homogeneous spaces
[ 講演概要 ]
Let G/H be a reductive homogeneous space. In all known examples, if
G/H admits compact Clifford-Klein forms, then it admits "standard"
ones, by uniform lattices of some reductive subgroup L of G acting
properly on G/H. In order to obtain more generic Clifford-Klein forms,
we prove that for L of real rank 1, if one slightly deforms in G a
uniform lattice of L, then its action on G/H remains properly
discontinuous. As an application, we obtain compact quotients of SO(2,2n)/U(1,n) by Zariski-dense discrete subgroups of SO(2,2n) acting properly discontinuously.
Let G/H be a reductive homogeneous space. In all known examples, if
G/H admits compact Clifford-Klein forms, then it admits "standard"
ones, by uniform lattices of some reductive subgroup L of G acting
properly on G/H. In order to obtain more generic Clifford-Klein forms,
we prove that for L of real rank 1, if one slightly deforms in G a
uniform lattice of L, then its action on G/H remains properly
discontinuous. As an application, we obtain compact quotients of SO(2,2n)/U(1,n) by Zariski-dense discrete subgroups of SO(2,2n) acting properly discontinuously.