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6b. Working dictionary: source-located, Lean-boundary edition

This is the rigorous companion to Stage 3 of the plan ("Build a dictionary"), restricted to what can be checked against the pinned Lean repository audited in 06. 07 is the cross-referenced beginner glossary; this file is narrower and stricter: a term is only called "formalized" here if an actual Lean declaration with that role exists and is reachable from the chain audited there — not merely mentioned in prose.

Snapshot: same pin as 06 — lana-agents/iut at d9465c111 (2026-10-03T19:53:47Z). All absence claims below are exhaustive, case-insensitive grep results over the full pinned checkout (Iut/, Iut4Sec1/, README.md, and the bundled paper excerpts under references/), re-run directly for this file, not recalled from an earlier pass.

How to read the table

Status tag Meaning
FORMALIZED A real Lean declaration fills this role; at least part of it is a proved theorem, not only a hypothesis.
NOT FORMALIZED (reference-text only) The term appears only inside the verbatim paper excerpts bundled under references/*.txt — never in a .lean file, never in README.md's own description of what the project models.
NOT FOUND The term does not appear anywhere in the pinned repository, including the bundled reference excerpts.
EXPLICITLY NOT CONSTRUCTED The project's own docstring states in so many words that this notion is out of scope / not built here.

Per 00-map.md's evidence labels: every "Purpose" cell describing literature meaning (not this repo's content) is ASSERTED_IN_IUT/SECONDARY, sourced from the bundled excerpts or general IUT literature, not independently re-derived here against Mochizuki's full original papers (only IUT IV is bundled — see log-link/log-theta-lattice rows). Any claim that a Lean definition is faithful to the paper's definition is UNVERIFIED unless stated otherwise — I checked that the named Lean object exists and is cited to a precise proposition number by the project's own docstring, not that the transcription is correct against the original text.

The five requested terms, plus one bonus (Frobenioid)

Term Status Source location Purpose Not licensed to infer
Hodge theater (Θ^±ellNF-Hodge theater / Θ^±ell-Hodge theater) NOT FORMALIZED (reference-text only) Only in references/iut4.txt:10,18,50,59,196,199-200,277 and references/iut4-section1.txt:1613-1616 — verbatim plain-text copies of Mochizuki's IUT IV paper bundled for citation. Zero matches in any .lean file or in README.md. (Literature only) Names the basic "arithmetic holomorphic structure" gadget; the log-theta-lattice relates distant copies of it. That Iut.InitialThetaData, Iut.LocalTheory, Iut.LargeVolumeContainerData, or any other structure in this repository is, formalizes, or stands in for a Hodge theater. Nothing in the repo defines, names, or type-checks anything called a theater.
theta-link (Θ-link) NOT FOUND No occurrence anywhere — not in Iut/, Iut4Sec1/, README.md (checked the spelled-out form and the Unicode "Θ-link"/"ΘLink" forms), and not even in the bundled references/ excerpts, since the repo carries only IUT IV material and no IUT III excerpt (the Θ-link's home paper). (Literature only) The horizontal, non-ring/scheme-theoretic gluing isomorphism of IUT III relating the Θ-pilot object across a horizontal arrow of the log-theta-lattice. That Iut/Cor312/RightHandSide.lean's thetaPilot/thetaPilot_le_shell field (the project's own "theta-pilot" input, taxis #35) formalizes or substitutes for the Θ-link. thetaPilot is an opaque input hypothesis field supplied as data (see 06 §6.2.1, node 0's "not licensed to infer" caveat), not a constructed gluing map — the repository never claims otherwise.
log-link NOT FORMALIZED (reference-text only) Only in references/iut4.txt:344,2984,2994,4191,4197,4322. Zero matches in Iut/, Iut4Sec1/, or README.md. (Literature only) The vertical arrow of the log-theta-lattice, built from the p-adic logarithm, passing between adjacent theaters. That this repo's real p-adic-logarithm construction (Iut/Concrete/LocalConstruct/PadicLog.lean, feeding LogShell.lean) is, builds, or uses the log-link. It is a single-theater, single-copy local computation establishing one theater's own log-shell — not an inter-theater gluing isomorphism. No declaration anywhere in the repository is named or documented as a/the log-link.
log-shell FORMALIZED (partial — single-theater, mono-analytic layer only) Interface: Iut/Cor312/Container.lean:79-119 (LargeVolumeContainerData.logShell + 4 sibling proof-obligation fields, taxis #43). Concrete construction + proved theorems: Iut/Concrete/LocalConstruct/LogShell.lean:10-50 (module docstring, taxis #4/#278), with e.g. automorphism-invariance RingHom.image_logShell_subset at :104 and algEquiv_image_factorLogShell_subset at :226. Concrete instantiation: Iut/Concrete/Container.lean:139-144. Discussed in README.md:219-222. Names the mono-analytic, compact, (at nonarchimedean places) order-containing region attached to each place of each tensor-packet (claimed: IUT III, Props. 3.1–3.3, 3.9; IUT IV, Prop. 1.2/1.5); bounds the theta-pilot input in the Corollary 3.12 variant (taxis #33/#35). Its invariance under the indeterminacy automorphisms is a genuinely proved Lean theorem, not an assumed hypothesis. That this formalizes "the log-shell as used in the log-theta-lattice" in general. It is explicitly scoped, by its own module docstring, to one theater's mono-analytic/local-field layer only — it does not construct, reference, or depend on the log-link (which would relate one theater's log-shell to another's), the log-theta-lattice, or any Frobenioid-theoretic/multiradial algorithm. Container.lean's own docstring: "nothing asserts that a theta-pilot image lies in the container, and no multiradial algorithm is constructed." Fidelity of the Lean definition to IUT I, Definition 5.4.5 / IUT III, Proposition 3.2 is UNVERIFIED by me against the original papers (only IUT IV is bundled in references/) — I confirmed the Lean kernel accepts the stated proofs and that the project's own docstring cites those exact proposition numbers, not that the transcription is correct.
log-theta-lattice NOT FORMALIZED (reference-text only) Only in references/iut4.txt (26 occurrences, e.g. lines 13, 19, 25, 33, 48, 60, 186, 195, 265, 277, 288, 297, 302, 333, 2952, 4196–4314, 4436). Zero matches in Iut/, Iut4Sec1/, or README.md. (Literature only) The two-dimensional diagram of theaters linked by log-links (vertical) and theta-links (horizontal) — IUT's central inter-universal comparison device; IUT IV Theorem 1.10 is, in the literature, extracted by walking it. That the Lean implication chain audited in 06 §6.2.1 (Corollary312Variant → theorem110 → c2 → … → ClassicalABC) formalizes, or traverses, the log-theta-lattice. It is an ordinary one-directional sequence of Prop-to-Prop Lean implications over a single, static bundle of input data (Corollary312VariantData) — no multiple theater copies, no indeterminacy groups, no horizontal/vertical arrow structure of any kind. "Corollary 3.12 variant" names only the project's own stipulated inequality (taxis #33), not a construction of, or argument over, the lattice the published Corollary 3.12 actually depends on.
Frobenioid (bonus — named in the plan's own Stage 3 example table) EXPLICITLY NOT CONSTRUCTED Iut/Cor312/LeftHandSide.lean:40 (docstring): "The q-pilot_object_ of IUT III (a Frobenioid-theoretic gadget) is not constructed; this module computes only its log-volume side…" This is the only occurrence of the word anywhere in Iut//Iut4Sec1/. (Literature only) The category-with-Frobenius-and-divisor-monoid structure through which IUT's multiradial algorithms transport arithmetic holomorphic structures between theaters; the published Cor. 3.12's q-pilot/Θ-pilot are Frobenioid-theoretic objects. That QPilotData/QPilotData.lhs (Iut/Cor312/LeftHandSide.lean) is, represents, or carries the categorical structure of a Frobenioid. It is a real number ($-\lvert\log(q)\rvert$) computed from admissible prime data — a numerical shadow the project's own docstring explicitly distinguishes from "the object itself."

Reading this table honestly

Five of these six terms are absent from the Lean source: they exist in this repository only as words in a bundled, verbatim plain-text copy of IUT IV (or, for theta-link, nowhere at all — not even there). This is not a defect the project hides: its own README.md and docstrings never claim to construct a Hodge theater, a theta-link, a log-link, or a log-theta-lattice, and the one Frobenioid mention is a self-reported scope exclusion. log-shell is the sole exception — a real, partially-proved Lean formalization exists, but strictly for one theater's local, mono-analytic layer, not for its role gluing distinct theaters together across the lattice. Do not let the familiarity of these names suggest broader coverage than the table above states. Cross-check against 06 §6.2.1 for how log-shell feeds the audited proof chain (and §6.5 there for the status of fuller evidence-label documentation), and against 07 for plain-language orientation on the terms this file marks absent.