Talk:Picard horn

Notability

Is this really notable? Some brief interest in popular media and then nothing. In fact, it seems rather FRINGEy. 94.196.51.165 (talk) 18:39, 3 February 2012 (UTC)

Brief interest? Please read the article: 129 years since the first discussion of the topic in a peer-reviewed journal by professional mathematicians is not just "brief interest in popular media". Boud (talk) 17:41, 16 February 2013 (UTC)

Sorry, I struck out a few words in my previous comment because the previous structure of the article made it sound like the space was invented only 8 years ago, and the fact that it's 129 years old is mentioned as a technicality. (Anyone new here should still read the article, of course :) .) So I understand the concern.

I've done a brief, quick restructure of the article so that it first focuses on the main thing: this is one of (maybe the?) oldest known hyperbolic 3-manifolds that can be given a constant curvature. 3-manifolds are an important part of mathematics, independent of any application in cosmology - e.g. see Grigori Perelman. The cosmological application is part of the peer-reviewed scientific literature in a serious journal, but the mathematical object exists independently of that. Boud (talk) 18:29, 16 February 2013 (UTC)

External links modified (January 2018)

Hello fellow Wikipedians,

I have just modified one external link on Picard horn. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

• Added archive https://web.archive.org/web/20120330102950/http://www.academie-sciences.fr/activite/archive/dossiers/Picard/Picard_oeuvre.htm to http://www.academie-sciences.fr/activite/archive/dossiers/Picard/Picard_oeuvre.htm

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

• If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
• If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 22:07, 24 January 2018 (UTC)

Proper description

There should be something on the article itself. I still cannot understand this thing. In one place it is described as identification of (x, y, z) with (x + an, y + bm, z) in the upper half plane model, but then how can it have a finite volume if volume grows infinitely with z -> 0? Grunewald and Huntebrinker failed to make it any clearer. They puzzle me with “r ≥ …” thing. Oh, man, why is it “r ≥ …”? How can it have a finite volume then? Why not “r ≤ …”? Tiling space with fundamental domain seems to earn modification of Square tiling honeycomb, but I can see no word about it, so maybe it's my mistake. Is there anywhere, finally, something understandable on topic? OCTAGRAM (talk) 01:21, 11 February 2018 (UTC)