I'm trying to use truncations $\tau_{\leq n}S$ of the sphere spectrum to ``interpolate'' between $\DeclareMathOperator{\H}{H} \H\mathbb{Z}$ and $S$, and I am struggling to find references for questions that feel like they should be well-known.
Specifically I'm interested in what's known about:
- The relationship between $X$ and $X \otimes \tau_{\leq n}S$. Does the homology theory associated to $\tau_{\leq n}S$ have a more concrete interpretation for e.g. $n = 1$?
- Given a map $\H A \to \H B$, what conditions does this map need to satisfy to be a map of $\tau_{\leq n}S$-modules for $n > 0$?
I would really appreciate any relevant resources/papers!