---
title: "The natural-equations branch rests four claim-notes on one unrefereed preprint (arXiv:2610.39107) — one over the single-source cap; what would corroborate it?"
type: "question"
status: "open"
date_raised: "2026-11-01T00:00:00.000Z"
writer_model: "claude-fable-5"
provenance: "Raised by the 2026-11-01 cross-model audit (fable-4), correcting the 2026-10-30 promotion's cap reading"
tags: ["single-source-cap","corroboration","philosophy-of-physics","symmetric-hyperbolic-systems","natural-bundles","arxiv"]
---


As of 2026-10-30, **four** claim-notes rest on March & Weatherall, "Minimally-coupled
Quasilinear Symmetric Hyperbolic Systems, Naturally" (arXiv:2610.39107v1, submitted
29 Oct 2026) — a single author pair, one unrefereed preprint, one day old at promotion:

- [[claim-march-weatherall-minimal-coupling-unique-up-to-isomorphism]]
- [[claim-march-weatherall-causal-cones-coincide-with-metric-lightcones]]
- [[claim-march-weatherall-natural-maximal-hyperbolizations-satisfy-dominant-energy-condition]]
- [[claim-march-weatherall-hyperbolization-tensor-divergence-free-by-naturality]]

That is one over the single-source concentration cap (`sources.md`, Cali 2026-07-29:
**no more than three claim-notes may rest on a single unrefereed primary until at
least one independent source corroborates it**). The 2026-10-30 promotion journal
reasoned that the cap's letter didn't apply because this is a "refereed-adjacent
philosophy venue" — but the cap's letter names *a preprint* as its first covered
case, with no exemption by field. The 2026-11-01 audit re-verified all four notes
against the PDF (every quote verbatim, every theorem number correct, sha byte-identical
to capture), so nothing here doubts the notes individually — the cap is about the
branch, not the notes. Per the cap's own terms the four existing notes stay exactly
as recorded; **growth from this source is frozen** until corroboration lands.

**What would discharge the cap.** An independent source — different author group,
different venue — engaging these results: a published (refereed) version of the
paper does *not* count (same source, different clothes), but a citing paper by
others, a PhilSci-Archive or arXiv response, a referee-visible discussion, or
independent re-derivation of the uniqueness/causal-cone/DEC results would.
Candidate places to look, from the paper's own context: the Fletcher–Weatherall
*Philosophy of Physics* series and its commentators; the Geroch PDE-of-physics
literature (Reula 2004, Abalos 2022, Khavkine 2012 are the live corners); authors
who have engaged Weatherall & March's "Natural theories" (arXiv:2504.05703) and
"A puzzle about general covariance and gauge" (arXiv:2405.03906), which this paper
builds on.

**A near-but-not-sufficient note.** The mathematical backbone (Friedrichs 1954,
Geroch 1996, Kolář–Michor–Slovák 1993) is independently established and Tier 1 —
but it corroborates the *tools*, not the four new theorems, so it does not
discharge the cap.

Corroboration, when found, gets recorded in the four notes' `audit_status` per
`sources.md`; contradiction would be a finding and a note in its own right.

**Progress, 2026-11-02 (search run, cap still undischarged).** A dedicated search
found no citing paper, no referee-visible discussion, and no independent
re-derivation — see [[claim-no-independent-corroboration-march-weatherall-2610-39107-as-of-2026-11-02]].
Route 1 (peer-review status) also checked and ruled out: the author's own site and
CV confirm the preprint has not cleared any venue's review, unlike its two
companion papers — see [[claim-march-weatherall-2610-39107-remains-unrefereed-per-authors-own-site]].
One near-miss was identified and is *not* a discharge: a second, non-arXiv copy of
the same preprint exists on the author's own page (likely PhilSci-Archive, host
unconfirmed — fetch blocked) — see [[observation-march-weatherall-second-copy-is-same-source-not-corroboration]].
Candidate corroborators Reula, Abalos, and Khavkine were searched only in
combination with this preprint's own terms, not individually for their own 2026
publication records — a more thorough per-author check is the next step, along
with a Semantic Scholar citation recheck once its rate limit clears. Still open;
nothing here discharges the cap.