Multiplicative function anticorrelation and bounds on $1/ζ'(ρ)$
Gordon Chavez
TL;DR
The paper links upper bounds for $1/|\zeta'(\rho)|$ to anticorrelations between multiplicative functions and their past sums under RH and SZC. By developing logarithmically averaged correlations for $(\mu(n), M(n-1))$ and $(\lambda(n), L(n-1))$, and expressing these sums through zeros of $\zeta(s)$, the authors derive explicit asymptotics that imply $1/\zeta'(\rho)=o(|\rho|)$ or $o(|\rho|\log\log|\gamma|)$ when the right-hand sides are negative. The work provides a novel bridge between pseudorandomness of $\mu$/$\lambda$ and zero-derivative bounds, supported by numerical evidence showing consistent anticorrelation. The results have potential implications for moment bounds of $1/|\zeta'(\rho)|$ and for understanding zero-distribution phenomena via multiplicative-function correlations.
Abstract
Let $ζ(s)$ denote the zeta function and let $μ(.)$ and $M(.)$ denote the Möbius function and the summatory Möbius function respectively. Similarly, let $λ(.)$ and $L(.)$ denote the Liouville function and the summatory Liouville function respectively. Finding upper bounds on $1/\left|ζ'(ρ)\right|$ is a longstanding open problem. Under the Riemann hypothesis and simplicity of the nontrivial zeros $ρ=1/2+ i γ$ of $ζ(s)$ we show that numerical evidence for the result $$ \sum_{n\leq N}\frac{μ(n)M(n-1)}{n}<0 $$ as $N\rightarrow \infty$ serves as numerical evidence for the bound $$ \frac{1}{ζ'(ρ)}=o\left(\left|ρ\right|\right) $$ as $\left|γ\right|\rightarrow \infty$ and similarly, numerical evidence for $$ \sum_{n\leq N}\frac{λ(n)L(n-1)}{n}<0 $$ as $N\rightarrow \infty$ serves as numerical evidence for the bound $$ \frac{1}{ζ'(ρ)}=o\left(\left|ρ\right|\log \log \left|γ\right| \right) $$ as $\left|γ\right|\rightarrow \infty$. We thus describe a new form of numerical evidence for effective upper bounds on $1/\left|ζ'(ρ)\right|$ that involves demonstrating anticorrelation between multiplicative functions and their corresponding summatory functions, where the correlation is computed using a logarithmic average. Numerical results strongly indicate this anticorrelation, i.e., the negativity of the above sums.
