22 citations · 148 across the 40 of their papers we have counts for
4 papers · 1 filter
A nonseparable amenable operator algebra which is not isomorphic to a C*-algebra
Yemon Choi, Ilijas Farah, Narutaka Ozawa
It has been a longstanding problem whether every amenable operator algebra is isomorphic to a (necessarily nuclear) C*-algebra. In this note, we give a nonseparable counterexample.…
Extension of derivations, and Connes-amenability of the enveloping dual Banach algebra
Yemon Choi, Ebrahim Samei, Ross Stokke
If is a derivation from a Banach algebra to a contractive, Banach -bimodule, then one can equip with an -bimodule structure, such that the second tr…
Weak and cyclic amenability for Fourier algebras of connected Lie groups
Yemon Choi, Mahya Ghandehari
Using techniques of non-abelian harmonic analysis, we construct an explicit, non-zero cyclic derivation on the Fourier algebra of the real group. In particular this provides…
ZL-amenability constants of finite groups with two character degrees
Mahmood Alaghmandan, Yemon Choi, Ebrahim Samei
We calculate the exact amenability constant of the centre of when is one of the following classes of finite group: dihedral; extraspecial; or Frobenius with abelian…