Timeline for A conjecture about cross sections of a pyramid [closed]
Current License: CC BY-SA 3.0
13 events
| when toggle format | what | by | license | comment | |
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| Apr 13, 2017 at 12:57 | history | edited | CommunityBot |
replaced http://mathoverflow.net/ with https://mathoverflow.net/
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| Jun 24, 2014 at 15:52 | comment | added | The Masked Avenger | I imagine migration will happen. Ask yourself this: if your conjecture were false, how long would the chord at the base of the polygon have to be to be part of the cross section? | |
| Jun 24, 2014 at 15:41 | comment | added | shadow10 | @TheMaskedAvenger Thanks for taking the time to reply, but this is not entirely clear to me. Can this be put off hold? A clear answer would be helpful, comments are not clear to me. Sorry for my ignorance. If not then, can this be migrated to Math SE? Thanks in advance. | |
| Jun 24, 2014 at 15:31 | comment | added | The Masked Avenger | I suspect something more general is true, that you can't have an ngonal base, an (n+1)gonal cross section, and insist on some combination of equiangular or equilateral to apply to the polygons. | |
| Jun 24, 2014 at 15:27 | comment | added | The Masked Avenger | The pyramid faces provide n edges of the cross section; the remaining edge has to be a chord of the base, and either lie on an edge of the base, or "clip off" a corner of the base. If both polygons are to be regular, you will have length issues with the sides as you are "trying to fit three edges in the space of two" while at the same time keeping the edges in the cross section of the same length. | |
| Jun 24, 2014 at 5:41 | comment | added | shadow10 | Could you clarify a bit on your comment? @TheMaskedAvenger I don't get what you mean by "fitting in". And I ask everyone that if it is not suitable for this site, could you have it migrate to Math SE? Because I think it is interesting. Sorry for all inconvenience. | |
| Jun 23, 2014 at 23:28 | history | closed |
Benoît Kloeckner Neil Strickland Stefan Kohl♦ Ricardo Andrade S. Carnahan♦ |
Not suitable for this site | |
| Jun 23, 2014 at 17:54 | comment | added | The Masked Avenger | You might observe that "three edges of the n+1 gon have to fit in two edges of the n gon". | |
| Jun 23, 2014 at 17:06 | comment | added | Benoît Kloeckner | math.SE has a more general scope regarding math questions, you can try there if you do not solve the question by yourself. | |
| Jun 23, 2014 at 17:01 | review | Close votes | |||
| Jun 23, 2014 at 23:28 | |||||
| Jun 23, 2014 at 16:51 | comment | added | shadow10 | Sorry about posting wrongly, but I didn't know where to put it. I suppose you wouldn't tell me about the computation part, anyways thanks for the help. | |
| Jun 23, 2014 at 16:48 | comment | added | Benoît Kloeckner | In my opinion, this is not suitable to MO. Sketch of proof: 1. a section which is a $(n+1)$-gon must meet all faces of the pyramid; 2. it is therefore not parallel to he base; 3. By an explicit computation, show that not edges of the section can have the same length. | |
| Jun 23, 2014 at 15:57 | history | asked | shadow10 | CC BY-SA 3.0 |