novemberSep 8, 2024

Is this a triangle?

https://lemmy.vg/post/642510

Is this a triangle? - Lemmy.VG

I would have asked this on a math community but I couldn’t find an active one. In a spherical geometry, great circles are “straight lines”. As such, a triangle can have two or even three right angles to it. But what if you go the long way around the back of the sphere? Is that still a triangle?

Show threadtonynSep 8, 2024
The term you are looking for to describe such a shape is technically “spherical polygon”. Triangles are impossible in speherical geometry since the sum of the angles would always be greater than 180°.
Show threadBlóðbókSep 8, 2024
There is no rule that the angles of a triangle add to 180 degrees. It only holds true in Euclidean geometry, which this is not.
Show threadSkyNTPSep 8, 2024

There is no rule that the angles of a triangle add to 180 degrees.

I think this is debatable. If it was not, then the answer to OP’s question would be obvious, and this thread would be uninteresting. The words we use carry a lot of unwritten baggage.

Show threadbdonvr
I think OP clearly has an inkling of non-euclidian to even ask what they did, so I’m not sure euclidian rules are relevant to the discussion.
Sep 9, 2024 at 1:09amWeb