Piece selection and cardinal arithmetic

Abstract

We study the effects of piece selection principles on cardinal arithmetic (Shelah style). As an application, we discuss questions of Abe and Usuba. In particular, we show that if $\lambda \ge 2^{\kappa }$, then (a) $I_{\kappa ,\lambda }$ is not (λ, 2)-distributive, and (b) $I_{\kappa ,\lambda }^{+}\to {\left(I_{\kappa ,\lambda }^{+}\right)}_{\omega }^2$ does not hold.