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arxiv: 2312.02594 · v5 · submitted 2023-12-05 · 🧮 math.RT

A reduction theorem for the Navarro Alperin weight conjecture

Pith reviewed 2026-05-24 05:29 UTC · model grok-4.3

classification 🧮 math.RT
keywords Navarro Alperin weight conjecturereduction theoremsimple groupsabelian Sylow 2-subgroupsGalois automorphismsfinite group representations
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The pith

The Navarro Alperin weight conjecture reduces to simple groups.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper adapts an existing reduction theorem for the Alperin weight conjecture to its Navarro version, which requires compatibility with Galois automorphisms and group automorphisms. This shows that verifying the conjecture on finite simple groups is sufficient for all finite groups. As an application, the authors establish the conjecture for all finite groups that have abelian Sylow 2-subgroups. A sympathetic reader would care because this narrows the problem to checking simple groups and resolves it in an important special case.

Core claim

We give a reduction to simple groups for the Navarro Alperin weight conjecture. As an application, we prove the conjecture for the finite groups with abelian Sylow 2-subgroups.

What carries the argument

The reduction theorem that extends the Navarro-Tiep reduction to account for Galois and outer automorphisms.

Load-bearing premise

The Navarro-Tiep reduction for the ordinary Alperin weight conjecture adapts to the Navarro version without new obstructions from the added Galois and automorphism conditions.

What would settle it

A finite simple group in which the Navarro Alperin weight conjecture fails would show either that the adaptation does not hold or that the reduction theorem is incorrect.

read the original abstract

The Alperin weight conjecture has been reduced to simple groups by Navarro and Tiep. In this paper, we investigate the Navarro Alperin weight conjecture, which includes Galois automorphisms and group automorphisms in comparison with the original version, and give a reduction to simple groups. As an application, we prove the conjecture for the finite groups with abelian Sylow 2-subgroups.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 2 minor

Summary. The manuscript establishes a reduction of the Navarro Alperin weight conjecture (incorporating Galois automorphisms and group automorphisms) to the case of finite simple groups. The argument adapts the Navarro-Tiep reduction for the ordinary Alperin weight conjecture. As an application, the conjecture is verified for all finite groups whose Sylow 2-subgroups are abelian.

Significance. If the reduction holds, the result is a useful extension of existing reduction theorems in the area, narrowing the Navarro version of the conjecture to simple groups and supplying an explicit infinite family of groups for which the conjecture is now known to hold.

minor comments (2)
  1. [Introduction] The introduction would benefit from a brief explicit comparison (e.g., a short table or enumerated list) of the precise additional data (Galois action, outer automorphisms) that must be preserved in the reduction relative to the Navarro-Tiep argument.
  2. Notation for the action of Galois automorphisms on weights and on the set of irreducible characters should be introduced once and used consistently; several passages reuse the same symbol for distinct maps.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for the positive assessment of our manuscript, the recognition of its significance as an extension of the Navarro-Tiep reduction, and the recommendation for minor revision. No major comments appear in the report.

Circularity Check

0 steps flagged

No significant circularity; reduction adapts external prior result

full rationale

The paper states a reduction to simple groups for the Navarro Alperin weight conjecture by adapting the Navarro-Tiep reduction (different authors) for the ordinary Alperin weight conjecture. The application to groups with abelian Sylow 2-subgroups follows directly. No self-definitional steps, no fitted inputs renamed as predictions, and no load-bearing self-citation chains appear in the abstract or described argument. The derivation remains self-contained against the external benchmark of the prior reduction.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The paper is a pure-mathematics reduction theorem operating inside the standard axiomatic framework of finite groups and modular representation theory; no new entities or fitted parameters are introduced.

axioms (1)
  • standard math Standard axioms and theorems of finite group theory and p-modular representation theory
    The reduction and application are carried out within the established body of results on finite groups, blocks, and characters.

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discussion (0)

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Forward citations

Cited by 1 Pith paper

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

  1. A reduction theorem for the blockwise Navarro Alperin weight conjecture via H-triples

    math.GR 2025-12 unverdicted novelty 6.0

    A reduction theorem establishes that the blockwise Galois Alperin weight conjecture follows from inductive conditions on simple groups via isomorphisms of H-triples.

Reference graph

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