This video is a bit older now (over one year), but I just found about it. And I want to share it here, because it was very well explained, without boring stock videos or background music. It’s just like a teacher would teach you, but with some enthusiasm behind it. I enjoy his videos so far.

Video description:


Why is the speed of light the same in all reference frames? Let’s rediscover the thought experiments that led Einstein to his special theory of relativity

Chapters:

00:00 Introduction
01:15 1/3 Detect motion with particles? (Thought experiment)
04:01 Inertia doesn't allow detecting constant velocity motion
06:18  2/3 Detect motion with waves? (Thought experiment) 
09:18 Medium doesn't allow detecting constant velocity motion
10:15 Constant velocity motion is RELATIVE!
11:02 3/3 Detect motion with light? (Thought experiment)
13:12 Does light break relativity? 
13:46 Michelson & Morley's experiment (oversimplified) 
14:20 The logical conclusion - Speed of light is same in all frames
  • Exactly me too, lol. I was also confused about the aether, because I knew it was wrong but not why. Currently watching his explanation about how he arrive at E=mc2 right now (paused the video to link here). Not sure if this is the video you meant, but in case not I highly recommend this one too: I never understood why light has ENERGY but NO MASS… until now! - YouTube | Invidious