Check golden proportions

golden proportions in a castle

The Castelo del Monte (in Puglia region, southern Italy) shows several appearances of the golden ratio. Here is an applet used by students to check this. There are other applets, where less trivial occurrences appear (proportion in trapezoidal halls in the castle). This applet is related to the following paper: One Mathematical topic and several levels of implementation: Golden section’s viewing the sounds by Thierry Dana-Picard - Sara Hershkovitz - Zsolt Lavicza - Kristof Fenyvesi (Preprint 2019)