News The height of the pyramid of Cheops

[Vanadium 50]

omeone had to stick their neck out to pick the new angle.

Literally.

 

[russ_watters]

The Giza pyramids have slopes of 42, 43.3 and 41.6 degrees. (Slope taken from the corners to the top).

You clearly have looked into this more than I have; all I have is what the wiki article says:

Slope	51°52'±2'

https://en.wikipedia.org/wiki/Great_Pyramid_of_Giza
And:

One Egyptian pyramid that is close to a "golden pyramid" is the Great Pyramid of Giza (also known as the Pyramid of Cheops or Khufu). Its slope of 51° 52' is close to the "golden" pyramid inclination of 51° 50' – and even closer to the π-based pyramid inclination of 51° 51'. However, several other mathematical theories of the shape of the great pyramid, based on rational slopes, have been found to be both more accurate and more plausible explanations for the 51° 52' slope.

https://en.wikipedia.org/wiki/Golden_ratio

Can you explain the discrepancy?

Literally.

You did what I saw there.

 

[Vanadium 50]

Slope is "rise over run", right? The rise is well defined, but the run is not. I took them from the corners. Wikipedia takes it from the midpoint of the sides, presumably.

 

[Klystron]

From the wiki article on "golden ratios" I cited in an earlier post also referred to by other posters:

Eric Temple Bell, mathematician and historian, claimed in 1950 that Egyptian mathematics would not have supported the ability to calculate the slant height of the pyramids, or the ratio to the height, except in the case of the 3:4:5 pyramid, since the 3:4:5 triangle was the only right triangle known to the Egyptians and they did not know the Pythagorean theorem, nor any way to reason about irrationals such as π or φ.[99]

Bell, a noted mathematician and historian of mathematics, debunked many popular misconceptions surviving into the 20^th Century and, apparently, well into the 21^st.

 

[russ_watters]

Slope is "rise over run", right? The rise is well defined, but the run is not. I took them from the corners.

Oh...that's an interesting choice.

 

[collinsmark]

For some reason, this thread reminds me of this:

(source: https://xkcd.com/687/)