leanprover / leanprover/cslib

Local EF games: extracting partial isomorphisms from bounded Duplicator wins

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Dominant language
Lean
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709
Forks
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Avg merge
3d 6h
Merged PRs (30d)
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Description

I have a Lean-verified lemma formalizing a standard locality step in finite model theory / EF-game arguments: from a bounded-radius Duplicator winning condition (LocalDuplicatorWins), one can explicitly construct a finite partial isomorphism on the corresponding neighborhoods.

The result is:

  • constructive (no choice or noncomputable axioms),
  • radius-bounded,
  • independent of global EF-game theorems,
  • intended as reusable infrastructure rather than a standalone theory.

I would like guidance on:
(1) whether this fits CSLIB’s scope, and
(2) the appropriate namespace / level of generality before opening a PR.

Frozen reference artifact (self-contained Lean development):
https://github.com/inaciovasquez2020/cyclone-terminal-obstruction

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  4. Open a pull request that references the issue number.

Research direction

Read the frozen reference artifact linked in the issue, focusing on the LocalDuplicatorWins result and its construction of finite partial isomorphisms. Then determine the appropriate CSLib namespace and level of generality before proposing a PR; done means the scope and placement have maintainer guidance.

Written by the indexing model from the issue text.

Assessment

Domain
tooling
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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