Einstein's Lost Key - How we Overlooked the Best Idea of the 20th Century - YouTube
https://www.youtube.com/watch?v=o67TNtgPPckI Think Faster Than Light Travel is Possible. Here's Why. - YouTube
https://www.youtube.com/watch?v=9-jIplX6WjwThe speed of light is not constant – THE PHYSICS DETECTIVE
https://physicsdetective.com/the-speed-of-light/