Wikipedia:Articles for deletion/Oriented projective geometry

The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.‎

The result was keep. (non-admin closure) Svartner (talk) 19:19, 8 December 2025 (UTC)[reply]

Oriented projective geometry

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The so-called "oriented projective space" is just the sphere, which already has a page. Mathwriter2718 (talk) 16:14, 1 December 2025 (UTC)[reply]

Speedy keep – this is about a specific representation and set of methods, not about the space as an abstract structure. Stolfi's book has been cited many hundreds of times, and I see something like 15–20 of scholarly papers with the name "oriented projective geometry" in their title. The topic is clearly notable, and readers searching for it should find a Wikipedia article. It would be confusing and unhelpful to readers to merge this article into either sphere or spherical geometry, though this article could plausibly be linked from those. As an analogy, we wouldn't get rid of our article Polar coordinate system just because the coordinates are used to describe points in the Euclidean plane. –jacobolus (t) 16:55, 1 December 2025 (UTC)[reply]

Note: This discussion has been included in the list of Mathematics-related deletion discussions. Shellwood (talk) 17:07, 1 December 2025 (UTC)[reply]
Keep. The subject of at least two entire books from major academic publishers (Stolfi and Pappas). Easy pass of WP:GNG. —David Eppstein (talk) 19:02, 1 December 2025 (UTC)[reply]
Keep 500+ results for the exact phrase "oriented projective geometry" on Google Scholar is a pretty good indication that there's a topic here. Above, jacobolus makes a good analogy that illustrates why the "it's just a sphere" argument in the nomination is mistaken. For another, we wouldn't get rid of the article Bloch sphere just because we already have sphere. Stepwise Continuous Dysfunction (talk) 21:49, 1 December 2025 (UTC)[reply]

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.