20 Jun
2020
20 Jun
'20
1:57 p.m.
On 2020-06-20, at 19:07, Joel Jaeggli <joelja@bogus.com> wrote:
This is c in a vacuum. Light transmission through a medium is slower.
Ob-movie: https://en.wikipedia.org/wiki/The_Hummingbird_Project Grüße, Carsten