Relative Inner Amenability and Relative Property Gamma
Keyword(s):
Type Ii
◽
Let $H$ be a proper subgroup of a discrete group $G$. We introduce a notion of relative inner amenability of $H$ in $G$, we prove some equivalent conditions and provide examples coming mainly from semidirect products, as well as counter-examples. We also discuss the corresponding relative property gamma for pairs of type II$_1$ factors $N\subset M$ and we deduce from this a characterization of discrete, icc groups which do not have property (T).
2018 ◽
Vol 108
(3)
◽
pp. 363-386
Keyword(s):
2010 ◽
Vol 31
(03)
◽
pp. 793-805
◽
1984 ◽
Vol 259
(12)
◽
pp. 7826-7834
◽
2000 ◽
Vol 54
(1)
◽
pp. 37-43
◽