Phase variation and angular momentum of the Riemann, and, Dirichlet Xi functions
Giovanni Lodone
TL;DR
This paper introduces an angular momentum concept, encoded as the phase-variation rate of the Riemann and Dirichlet xi functions, to derive RH and GRH equivalences. By relating the phase derivative to a determinant-based angular momentum $\mathcal{L}[\cdot]$, it provides lemmas showing how multiplicative factors and Hadamard product decompositions influence $\mathcal{L}$, and extends these ideas from $\xi(s)$ to $\xi(s,\chi)$ for primitive Dirichlet characters. The core results establish that, under certain conditions, the sign of $\mathcal{L}$ tracks the distance from the critical line $\epsilon$, leading to equivalences: (i) if all zeros lie on the critical line, then $\mathcal{L}$ mirrors the sign of $\epsilon$; (ii) conversely, if $\mathcal{L}$ maintains this sign, then all zeros lie on the critical line. The work also connects these ideas to a whole-strip derivative relation and to a practical, line-based criterion via a modified function $\eta$, offering a Bombieri-style route to RH/GRH from critical-line data.
Abstract
The concept of angular momentum is used to find new RH equivalence statements, and, generalize some known results from Riemann to Dirichlet primitive Xi functions
