Definably amenable NIP groups
Definably amenable NIP groups
复制标题
DOI:
10.1090/jams/896
复制
发表时间:
2015-02
期刊:
影响因子:
--
通讯作者:
A. Chernikov;Pierre Simon
中科院分区:
文献类型:
--
作者:
A. Chernikov;Pierre Simon
We study definably amenable NIP groups. We develop a theory of generics, showing that various definitions considered previously coincide, and study invariant measures. Applications include: characterization of regular ergodic measures, a proof of the conjecture of Petrykowski connecting existence of bounded orbits with definable amenability in the NIP case, and the Ellis group conjecture of Newelski and Pillay connecting the model-theoretic connected component of an NIP group with the ideal subgroup of its Ellis enveloping semigroup.