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fix: require Hausdorff CW spaces for derived solidification - #658

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Vilin97:fix/derived-solid-cw-hausdorff
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Vilin97:fix/derived-solid-cw-hausdorff

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@Vilin97 Vilin97 commented Sep 29, 2026 •

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Fixes #657.

The comparison currently quantifies over Mathlib's Topology.CWComplex without requiring Hausdorffness. This admits the non-Hausdorff counterexample described in the issue, making the requested derived adjunction and universal homology comparison incompatible.

Require T2Space in the CWTopCat object property, expose that assumption as an instance, and add it to the pointwise derived comparison and both homology statements. Update the pointwise wrapper to construct objects of the restricted category. All twelve holes retain their names and mathematical roles.

Record this correction as statement revision 2. Preserve revision 1 in the revision history so the frozen v1 set remains valid. The digest covers the CW object property and the twelve hole signatures; its construction is documented beside the history entry. Generated workspaces are left to the repository's regeneration workflow, as requested by the contribution instructions.

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[problem] derived_solidification_free_CW_homology is false without a Hausdorff/T2 hypothesis

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