Pith. sign in

REVIEW 3 cited by

Monogenic fields with odd class number Part II: even degree

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2011.08842 v1 pith:TSB75O3P submitted 2020-11-17 math.NT

classification math.NT
keywords classdegreefieldsevennumberaveragesgroupinfinitely
verification ladder T0 review T1 audit T2 compute T3 formal
0 comments
abstract

In 1801, Gauss proved that there were infinitely many quadratic fields with odd class number. We generalise this result by showing that there are infinitely many $S_n$-fields of any given even degree and signature that have odd class number. Also, we prove that there are infinitely many fields of any even degree at least $4$ and with at least one real embedding that have units of every signature. To do so, we bound the average number of $2$-torsion elements in the class group, narrow class group, and oriented class group of monogenised fields of even degree (and compute these averages precisely conditional on a tail estimate) using a parametrisation of Wood. These averages are the first $p$-torsion averages to be calculated for $p$ not coprime to the degree (in degree at least $3$), shedding light on the question of Cohen-Lenstra-Martinet-Malle type heuristics for class groups and narrow class groups at "bad" primes.

Discussion (0). Sign in to comment.

Forward citations

Cited by 3 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Geometry-of-numbers methods over global fields II: Coregular representations

    math.NT 2026-04 unverdicted novelty 7.0 of 10

    Geometry-of-numbers methods are extended to count orbits in coregular spaces over arbitrary global fields, yielding bounds on average ranks and Selmer sizes for elliptic curves and hyperelliptic Jacobians.

  2. Counting the number of $n$-periodic $\mathbb{Z}_{p}$-and $\mathbb{F}_{p}[t]$-points of a discrete dynamical system with applications from arithmetic statistics, VI

    math.NT 2025-10 unverdicted novelty 4.0 of 10

    Establishes that averages of distinct n-periodic points for maps φ_{p^ℓ,c} and φ_{(p-1)^ℓ,c} over Z_p and F_p[t] are unbounded/zero or 1/2/0 as c varies, then derives counting results for irreducibles, zeta functions,...

  3. Counting the number of $1_{m}$-preperiodic $\mathcal{O}_{K}$-points of a discrete dynamical system with applications from arithmetic statistics, VII

    math.NT 2026-06 reject novelty 1.0 of 10

    The main theorem is false: for φ_{p,c}(z)=z^p+c over F_p with p|c, every point is fixed, so the number of 1_n-preperiodic points is 0, not p.

Pith tools