An ultrapower construction of the multiplier algebra of a $C^{\ast }$-algebra and an application to boundary amenability of groups

Facundo Poggi, Roman Sasyk

Using ultrapowers of $C^{\ast }$-algebras we provide a new construction of the multiplier algebra of a $C^{\ast }$-algebra. This extends the work of Avsec and Goldbring [Houston J. M…