Nakayama automorphisms of twisted tensor products

In this paper, we study homological properties of twisted tensor products of connected graded algebras. We focus first on the Ext-algebras of twisted tensor products with a certain form of twisting maps. We show those Ext-algebras are also twisted tensor products, and describe the twisting maps for such Ext-algebras explicitly. With those preparations, we describe Nakayama automorphisms of twisted tensor products of noetherian Artin-Schelter regular algebras.