Breaking Light

  • Thread starter Doguso
  • Start date
  • #1
2
0

Main Question or Discussion Point

"Breaking Light"

My friend tried explaining to me that you can "break" the speed of light. He showed me a youtube video, "minutephysics" saying that if you could point a laser at the moon, by flicking your wrist, the image/spot of the laser on the moon would be moving faster than light. Is he right?
 

Answers and Replies

  • #2
phinds
Science Advisor
Insights Author
Gold Member
2019 Award
15,911
5,600


My friend tried explaining to me that you can "break" the speed of light. He showed me a youtube video, "minutephysics" saying that if you could point a laser at the moon, by flicking your wrist, the image/spot of the laser on the moon would be moving faster than light. Is he right?
No. That is EXACTLY like saying that if you look at one star and then at another star, your gaze has gone faster than the speed of light. Nothing "moves" as the beam is swept across the moon. This is an OLD canard and has to be debunked here about once a month.
 
  • #3
Pengwuino
Gold Member
4,989
15


My friend tried explaining to me that you can "break" the speed of light. He showed me a youtube video, "minutephysics" saying that if you could point a laser at the moon, by flicking your wrist, the image/spot of the laser on the moon would be moving faster than light. Is he right?
Special Relativity forbids physical processes that transmit some sort of information from exceeding the speed of light. Pointing a laser at the moon and flicking your wrist does not transfer any physical thing at faster than the speed of light. Different light hits the moon at the different points you point the laser at. The same light would have to move from one edge of the moon to the other for special relativity to be violated, but that is not something you can do since you're constantly sending out a stream of different photons.
 
  • #4
2
0


Thank you. How you explained the different particles of light is what's moving was a better way than I could to my friend. Least I have good proof of this... I'm semi-surprised that you're asked this so frequently haha. Sorry if I annoyed you guys with such a stupid theory.
 
  • #5
ghwellsjr
Science Advisor
Gold Member
5,122
146
Last edited by a moderator:
  • #6
70
2


This is what happens when you try to fit something you don't know a lot about into a minute and the pixel analogy is ludicrous.
 

Related Threads on Breaking Light

  • Last Post
Replies
13
Views
1K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
10
Views
2K
  • Last Post
Replies
5
Views
1K
Replies
3
Views
2K
Replies
10
Views
988
Replies
43
Views
3K
Replies
153
Views
21K
Replies
1
Views
2K
Replies
1
Views
2K
Top