Apparently, the speed of light has not been measured directly ... only by bouncing light off a mirror and measuring the two-way speed. I.e. to a point and then back again.

Measuring from point to point is fraught with the difficulties of synchronising clocks - relativity gets in the way when clocks move. Without accurate clocks, you can't get accurate speed. Bouncing light back to the start point means you only need one clock - so total speed is measurable - but not the outward, nor the return speed. Only the total.

So it's theoretically possible that the speed of light is direction dependant. But impossible to verify.

Very interesting channel - and their take on the speed of light:
YouTube

I'm sure the video will explain it much better then I could.

@phoulamboule said
I have 2 games with the same opponent. After 1 move each, the app closes and I go to my phone home screen. I can’t delete the games or message the opponent. Any ideas what’s going on?

Here's the direct links to your games (the only pair you have to the same opponent))... perhaps you moved them into another folder accidently?
Game 15655190
Game 15650902
I'm pretty sure that you can get to a playable board from the above links.

@bigdogg said
Feynmann said, if not for the unfortunate choice of the second as the unit of time, that the equation is just:

e = m

Energy equals mass.

If that were true then I'd have a lot more energy.
🙁