I found this video by accident, and it turned out to be good presentation “Why Going Faster-Than-Light Leads to Time Paradoxes” about the paradox if speed faster than “speed of light” would be possible.
I liked that it was explained with the help of simple diagrams, interesting topic and worth to have a look. Please note that while the explanation is good, it is also very fast for non native english persons…
After 25min video, I’m left with the thinking that “I would like to see more on this topic” 🙂