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A comment on Glass viscosity calculations debunk the myth of flow in medieval windows (2017). Parent comment

Re:Glass viscosity calculations debunk the myth of flow in m... by elmomle on Thursday October 29, 2020 @10:06PM (#24938368)
Allow me to be dumb for a second--isn't that the case? I mean, if you label the vertices/edges then yes a regular pentagon has five distinct lines of symmetry, but typically people talk about lines of symmetry in a context where vertices are unlabeled, no?
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Re:Glass viscosity calculations debunk the myth of flow in m... by pgreenwood on Thursday October 29, 2020 @10:25PM (#24938493)
There are 2n symmetries for an n-sided polygon. In this case five rotations and five reflections. https://math.stackexchange.com/questions/490054/symmetries-o...
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Re:Glass viscosity calculations debunk the myth of flow in m... by simongr3dal on Thursday October 29, 2020 @10:28PM (#24938505)
I agree, but I think in most cases where grade schoolers are made to draw mirror symmetries on work sheets that all symmetries are included, even if they are simply the same symmetry but rotated.
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Re:Glass viscosity calculations debunk the myth of flow in m... by ordu on Thursday October 29, 2020 @10:26PM (#24938501)
In spite of an argument "the top is bigger than the bottom", it seems to me that he/she meant that there is no horizontal line of symmetry, so there is only vertical one.
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Re:Glass viscosity calculations debunk the myth of flow in m... by MacsHeadroom on Thursday October 29, 2020 @10:23PM (#24938486)
A regular pentagon has 5 lines of symmetry. One from the center of each edge to the point on the other side.
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