2026/06/24 by Eugenia Ellis, Emanuel Rodríguez Cirone · 2 voices
Mathematics · #math.KT #math.RA
Let G be a group. We prove that matrix stability for either G-algebras or G-graded algebras guarantees Morita invariance. As a consequence, bivariant algebraic K-theory (either G-equivariant or G-graded) is Morita invariant. In particular, we show that if G is a finite group acting freely on a finite simplicial set X, then ℓX\rtimes G and ℓX/G are kk-equivalent. Here, ℓY denotes the ℓ-algebra of piecewise polynomial functions on Y with coefficients in the ground ring ℓ.