The Taylor towers for rational algebraic $K$-theory and Hochschild homology

Abstract

We compute the Taylor tower for Hochschild homology as a functor from augmented commutative simplicial $\dbQ$-algebras, to chain complexes over $\dbQ$. We use this computation to obtain the layers for the Taylor tower of rational algebraic $K$-theory. We also show that the Hodge decomposition for rational Hochschild homology is the decomposition of the Taylor tower of the augmentation ideal functor into its homogeneous layers when evaluated at a suspension.