The Hydra Map and Numen Formalisms for Collatz-Type Problems

This paper details a generalization of the formalism presented in the author’s 2024 paper, “The Collatz Conjecture and Non-Archimedean Spectral Theory - Part I - Arithmetic Dynamical Systems and Non-Archimedean Value Distribution Theory”, to the case of Hydra maps on the ring of integers ${\mathcal{O}}_K$ of a global field $K$. In addition to recounting these definitions, background material is presented for the necessary standard material in algebraic number theory and integration and Fourier analysis with respect to the $p$-adic Haar measure. This paper is meant to serve as a technical manual for use of Hydra maps and numens in future research.