Detecting $\beta$ elements in iterated algebraic K-theory

Abstract:

The Lichtenbaum–Quillen conjecture (LQC) relates special values of zeta functions to algebraic K-theory groups. The Ausoni–Rognes red-shift conjectures generalize the LQC to higher chromatic heights in a precise sense. In this paper, we propose an alternate generalization of the LQC to higher chromatic heights and give evidence for it at height two. In particular, if the $n$-th Greek letter family is detected by a commutative ring spectrum $R$, then we conjecture that the $n+1$-st Greek letter family will be detected by the algebraic K-theory of $R$. We prove this in the case $n=1$ for $R=\mathrm {K}(\mathbb {F}_q)$ modulo $(p,v_1)$ where $p\ge 5$ and $q=\ell ^k$ is a prime power generator of the units in $\mathbb {Z}/p^2\mathbb {Z}$. In particular, we prove that the commutative ring spectrum $\mathrm {K}(\mathrm {K}(\mathbb {F}_q))$ detects the part of the $p$-primary $\beta$-family that survives mod $(p,v_1)$. The method of proof also implies that these $\beta$ elements are detected in iterated algebraic K-theory of the integers. Consequently, one may relate iterated algebraic K-theory groups of the integers to integral modular forms satisfying certain congruences.