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LemmaStatement: AI-generatedProof: AI-generated
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

Deleting relative root hyperplanes removes all cone-boundary points

Statement

Let (W,S) be a finite-rank Coxeter system in its canonical real representation V=RS, with basis (αs), dual Θ, root system Φ, contragredient action, and Tits cone U. For I⊆S put EI={f:f(αi)=0 (i∈I)} and CI={f∈EI:f(αs)>0 (s∉I)}. Fix J⊆S and put E=EJ, T=U∩E, and T∘=int⁡ET. With ΦJ and A as in the restricted-root-trace lemma, put D=⋃K∈AK. Then T∖D=T∘∖D.

External input

Iyama–Wemyss, the sentence immediately after Definition 1.6, states that the J-chambers xCI⊆EJ with ∣I∣=∣J∣ are the connected components of (U∩EJ)∖⋃α∈ΦJHα.

Facts & Assumptions

[F1]

The restricted deletion set agrees with the root deletion set by The relative root deletion set is the restricted-hyperplane union.

[F2]

Every source J-chamber is contained in T∘ by Full-dimensional J-chambers lie in the relative interior.

[F3]

Every point of a topological space belongs to its connected component, including when that space is a subspace, as defined and justified in Connected components, quasicomponents, and totally disconnected spaces.

[F4]

In the topological space E, the interior of T is the union of open subsets of E contained in T; in particular T∘⊆T, by Interior, closure, boundary, exterior, derived set and isolated point in a topological space.

Proof

Given: The objects and hypotheses of the statement. Goal: Establish its conclusion.

Iyama–Wemyss, the sentence immediately after Definition 1.6, states that the J-chambers xCI⊆EJ with ∣I∣=∣J∣ are the connected components of (U∩EJ)∖⋃α∈ΦJHα.

1.1F1F2F3given

By [F3], every point p∈T∖D belongs to a connected component of that space. By [F1] and the external input, that component is a source J-chamber. By [F2] it is contained in T∘, so p∈T∘∖D.

2.1F4step 1.1given∎

Conversely T∘⊆T by the definition of interior in [F4], so T∘∖D⊆T∖D. Together with the first inclusion this proves equality, also for the zero-dimensional case.

Source notes

The external statement is used only as explicitly recorded above. It is an independent prerequisite source, not the article under study. The local topology and linear-algebra argument is authored here; the source proof has not been reviewed.

Depends on

Used by · 2

Dependency tree · 2 levels

Each result is drawn at its shortest distance from this item. Arrows run from prerequisites to the items that use them; this item has a heavier outline. External source nodes link directly to the cited text. The view shows up to two dependency steps; open a prerequisite to continue.

External dependencies

Osamu Iyama and Michael Wemyss, Tits Cone Intersections and Applications, author-hosted draft · Sentence following Definition 1.6, printed p. 6 (PDF p. 30)

Iyama–Wemyss, the sentence immediately after Definition 1.6, states that the $J$-chambers $xC_I\subseteq E_J$ with $|I|=|J|$ are the connected components of $(U\cap E_J)\setminus\bigcup_{\alpha\in\Phi^J}H_\alpha$.

Hypotheses: Finite Coxeter graph, canonical real reflection representation and dual action; arbitrary vertex subset J, not required spherical. Our I is the source secondary subset, and our J is the source fixed subset.

Reading limits: Read the extracted source text of §1.1 and §§1.3–1.4 (printed pp. 3–6), including Definitions 1.3–1.6 and the following component assertion. Checked the finite-rank setup and notation correspondence. No source proof review or local reconstruction; no infinite-rank topology or local-finiteness result imported.

Sources