HNN Extensions of von Neumann Algebras

Abstract

Reduced HNN extensions of von Neumann algebras (as well as $C^{\ast }$-algebras) will be introduced, and their modular theory, factoriality and ultraproducts will be discussed. In several concrete settings, detailed analysis on them will be also carried out.

Slightly revised version

References in corpus (3)

• Some prime factorization results for type II_1 factors
• On a Class of Type II${}_1$ Factors with Betti Numbers Invariants
• Automorphisms of free product-type and their crossed-products

Cited by in corpus (6)

• Factoriality, type classification and fullness for free product von Neumann algebras
• Unbounded derivations, free dilations and indecomposability results for II${}_1$ factors
• HNN extensions and unique group measure space decomposition of II_1 factors
• Oracle computability of conditional expectations onto subfactors
• W${}^{\ast }$-superrigidity for wreath products with groups having positive first ${\ell }^2$-Betti number
• A relationship between HNN extensions and amalgamated free products in operator algebras