Image:QuartetOfMorinSurfaces(WithoutPassageBarriers).PNG
From Wikipedia, the free encyclopedia
This is a file from the Wikimedia Commons. The description on its description page there is shown below. |
La bildo estas kopiita de wikipedia:en. La originala priskribo estas:
Four different views of the Morin surface (with "passage barriers" cut out).
What is meant here by "passage barrier"? It is an informal designation for parts of a self-intersecting inmersion in 3-space of a surface: which parts of such surface are bounded by closed loops of double points. Examples: the Klein bottle has one passage barrier, and the Boy's surface has three passage barriers. The Morin surface has four passage barriers.
The Klein bottle in upright position has a "cave entrance" at its bottom, which narrows into an upward tubular passageway which then intersects the wall of the "inner chamber". The intersection is a nearly circular loop of double points, and the surface of the main chamber's wall bounded by this loop is what is being referred to as a "passage barrier". (After passing through the barrier, the passageway continues upward then starts doing a U-turn until it faces downwards and begins to widen, eventually becoming the bottle's main chamber. Before reaching the bottom, though, the main chamber begins to narrow before turning itself back into a cave entrance.)
Designed by AugPi in Texas.
Rendered with Mathematica.
©AugPi, MMV.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
العربية | Česky | Deutsch | English | Español | Français | Italiano | 日本語 | 한국어 | Nederlands | Polski | Português | Slovenčina | Svenska | עברית +/- |
date/time | username | edit summary |
---|---|---|
04:30, 15 June 2005 | en:User:AugPi | ("main chamber"-->"inner chamber", to match the terms used in the Boy's surface article) |
04:25, 15 June 2005 | en:User:AugPi | (which links have been added) |
03:55, 15 June 2005 | en:User:AugPi | (Rendered with Mathematica.) |
03:31, 15 June 2005 | en:User:AugPi | (signature) |
03:06, 15 June 2005 | en:User:AugPi | (Four different views of the Morin surface (with "passage barriers" cut out).) |
[edit] Historio de la dosiero
Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version.
Click on date to download the file or see the image uploaded on that date.
- (del) (cur) 03:06, 15 June 2005 . . en:User:AugPi AugPi ( en:User_talk:AugPi Talk) . . 902x743 (115714 bytes) (Four different views of the Morin surface (with "passage barriers" cut out).)