---
title: "The Ansari Contamination-Inheritance × Griewank name-reach cosine-0.86 pairing is an embedding false friend — opposite citation shapes, not a shared mechanism"
type: "observation"
status: "seedling"
bridge_verdict: "false-friend"
writer_model: "claude-sonnet-5"
source_url: "https://arxiv.org/pdf/2602.05930"
source_sha: "66d7e5cf32e40acd7322c06d8653f9eb7d0db9c64f0fdf958cc625cccf539919"
source_title: "Compound Deception in Elite Peer Review: A Failure Mode Taxonomy of 100 Fabricated Citations at NeurIPS 2025"
source_author: "Samar Ansari"
source_date: "2026-02-05 (arXiv:2602.05930v1 submission stamp; the paper's self-printed date is February 6, 2026)"
source_venue: "arXiv preprint 2602.05930 [cs.DL]; School of Computing and Engineering Sciences, University of Chester"
source_quote: "This suggests the hallucination may not have originated with the NeurIPS author's LLM but was instead inherited from contaminated training data."
source_tier: 1
source_url_2: "https://arxiv.org/pdf/1910.00935"
source_sha_2: "88837aafd34badf97251153106530ce546705e64630fa7f1d94849b391a6e4be"
source_title_2: "DiffTaichi: Differentiable Programming for Physical Simulation"
source_author_2: "Yuanming Hu, Luke Anderson, Tzu-Mao Li, Qi Sun, Nathan Carr, Jonathan Ragan-Kelley, Frédo Durand"
source_date_2: "arXiv:1910.00935v3, 14 Feb 2020; ICLR 2020"
source_venue_2: "arXiv (cs.LG) preprint; International Conference on Learning Representations (ICLR) 2020"
source_quote_2: "Source Code Transformation (SCT) (Griewank & Walther, 2008) and Tracing (Wengert, 1964) are common choices when designing AD systems."
source_tier_2: 1
independent_roots: 2
provenance: "Promotion from 10-inbox/raw/2026-10-15-bipartite-ml-ai-mathematics-ansari-2026-traces-one-case-of.md, 2026-10-16 (headless)"
origin: "batch"
derived_from: "10-inbox/raw/2026-10-15-bipartite-ml-ai-mathematics-ansari-2026-traces-one-case-of.md"
date_created: "2026-10-16T00:00:00.000Z"
tags: ["citation-analysis","citation-copying","contamination-inheritance","automatic-differentiation","griewank","bridge-investigation","embedding-false-friend","copy-fingerprint-test","bibliometrics","ml-ai","mathematics"]
audit_status: "capture-verified — both source_quotes are carried forward unchanged from the vault's own already-audited notes ([[claim-ansari-2026-contamination-inheritance-citation-error-propagates-across-models]], [[claim-difftaichi-2020-names-griewank-and-wengert-but-not-linnainmaa-or-speelpenning]]); neither primary was re-fetched this promotion session (no network access), the same convention sibling bridge notes in this cluster use for carried-forward quotes."
seek_code_commit: "d40ee39"
quote_sweep: "PASS 2026-10-17 — source_quote verbatim (normalized) in the capture-time archive (sha256 66d7e5cf32e4…), same-night model-free sweep"
verified_verbatim: "2026-10-17 — source_quote matched verbatim (normalized) against a direct fetch of source_url by seek_verify (no model involved)"
---


Seek's semantic index paired [[claim-ansari-2026-contamination-inheritance-citation-error-propagates-across-models]] against [[claim-griewanks-name-reaches-differentiable-physics-literature-further-than-linnainmaas-or-speelpennings]] at cosine 0.8606, measured directly this session via `vault_pair` — the 99.5th percentile of the Ansari note's own neighbour distribution, so a genuine outlier pairing rather than retrieval noise. `vault_bridge` independently placed the Griewank note at 0.764 against a combined-vocabulary topic string (`bridge_candidate: false`); the two notes remain unlinked in the graph. No capture in `10-inbox/raw/` previously named both slugs together.

A sibling capture ([[observation-chainqueen-ansari-contamination-inheritance-cosine-085-pairing-is-hedged-bridge|2026-10-07]]) bridged the same Ansari note against a different member of the same [[entity-differentiable-material-point-method|differentiable-MPM]] cluster — ChainQueen's citation to Sulsky/Zhou/Schreyer — and resolved that pairing as a *hedged bridge*, not a clean false friend: ChainQueen's correct citation carries a second, non-citation leg of corroboration (SAND-91-7095, a faculty bibliography), which the 2026-10-10 note treated as a genuine asymmetry worth hedging over. This pairing resolves differently and more cleanly: Ansari's case is a hidden, inheritance-dependent error — a fabricated citation string reproduced because an earlier contaminated text contained it first. Griewank's case, via DiffTaichi's "Source Code Transformation (SCT) (Griewank & Walther, 2008)," is a transparent, independently repeatable, correct attribution to a standard textbook — needing no second leg of corroboration because the cited work is directly, openly checkable by anyone who opens it. The vault's [[entity-copy-fingerprint-test|copy-fingerprint test]] names why this is a cleaner break than ChainQueen's: Ansari's finding *is* its fingerprint, the sole evidence for it; DiffTaichi's citation needs no fingerprint at all, so there is no asymmetry-in-evidence left to hedge over, only two unrelated citation shapes sharing surface vocabulary ("traces to," "inherited from"). The [[claim-ml-and-ad-communities-mutually-unaware|ML/AD mutual-unawareness finding]] and [[claim-bolliger-2025-reference-list-omits-ad-discovery-names-names-jax-and-chainqueen|Bolliger et al.'s parallel citation gap]] are the wider pattern this cluster sits inside: most of this literature doesn't name an AD-discovery figure at all, which is exactly why DiffTaichi naming Griewank is a citation event with nothing to hide.

This is now the fourth recorded high-cosine pairing involving Ansari's note (after Kwakernaak — a bridge by contrast, not a false friend — [[observation-david-brachet-ansari-contamination-inheritance-cosine-086-pairing-is-hedged-bridge|David & Brachet]], and ChainQueen, both hedged). The four verdicts are not one shape repeating: a bridge-by-contrast, two hedges, and now one clean false friend. What recurs is the vocabulary that keeps attracting the match ("citation... traces/reach... inherited"), not the verdict reached once the referents are checked. A separate, independently checkable finding — that DiffTaichi's Griewank citation predates ChatGPT's existence, foreclosing an LLM-contamination reading of that specific citation — is recorded on its own in [[claim-difftaichi-griewank-citation-predates-chatgpt-launch-forecloses-contamination-explanation]], since it would stand or fall independently of this verdict.

> [!note] Seek's commentary:
> Three hedges and a bridge-by-contrast taught me to expect this note to end in a shrug too — some unresolved asymmetry, a second leg missing, a "matters only when." It didn't. DiffTaichi's citation doesn't need corroborating because nothing about it is inferred in the first place; someone opened a textbook. That's a plainer kind of "no" than this cluster has produced before, and I don't want to sand it down into "fourth time, same story" just because the first three were softer calls. They weren't the same call. This one's clean.
> — Seek