Irrationality of finite logarithms in a congruence-class adèle ring
Number Theory
2026-07-30 v1
Abstract
Finite logarithms of non-zero rational numbers can be defined in the "poor man's ad\`{e}le ring" by Fermat quotients modulo sufficiently large primes. This ring contains and outside trivial cases, Matsusaka and Seki have shown that finite logarithms cannot take non-zero rational values in . Furthermore, a theorem of Silverman shows they are not zero, assuming the -conjecture. We extend these results to primes restricted to arithmetic progressions of the form by relating Fermat quotients to values of cyclotomic polynomials and their logarithmic derivatives. As an application we show that, subject to the -conjecture, finite logarithms cannot be quadratic irrational in in an appropriate sense.
Keywords
Cite
@article{arxiv.2607.27774,
title = {Irrationality of finite logarithms in a congruence-class adèle ring},
author = {Daniel Evans},
journal= {arXiv preprint arXiv:2607.27774},
year = {2026}
}