What's the secret behind v < c

topsquark

Forum Staff
Apr 2008
3,024
638
On the dance floor, baby!
Actually, it’s not necessary to care too much about if c is phase speed or group speed or the specific value of c in SR.
...But \(\displaystyle v_g\) and \(\displaystyle v_p\) are, in general, not equal. So we do have to make a distinction. However if you are interested only in one frequency, then yes, they are the same.

Actually, c ≈ ****** m/s is a very small value in planet scale. For the motion elements such as mass, force, acceleration, momentum, kinematic energy, etc, their values can trend to infinite theoretically. Why cosmos / physics mistreat speed? This problem can be solved in 4D space SR.
What is it about speed that we are "mistreating?" I mean, any physical constant can never become infinite so why are you worried about the speed of light not becoming infinite?

-Dan
 
Mar 2019
815
42
cosmos
@dragon:
".. worried about speed of light not becoming infinite?"
I can't find this sentence in my post.
 

topsquark

Forum Staff
Apr 2008
3,024
638
On the dance floor, baby!
For the motion elements such as mass, force, acceleration, momentum, kinematic energy, etc, their values can trend to infinite theoretically. Why cosmos / physics mistreat speed?
The first sentence talks about properties that can tend to the infinite. Then you mention speed that Physics "mistreats." I had taken that to mean you thought that c ought to be able to tend to the infinite as well.

Sorry if I misunderstood. Can you please explain what you meant?

-Dan