# Why is the speed of light limited to a countable number

1. Aug 26, 2011

### AgentPancake

why isnt it like infinity or something.

2. Aug 26, 2011

### Hootenanny

Staff Emeritus
As I said in your other thread, the fact that the maximum speed, which coincides with the speed of light in vacuum, is a finite constant follows from the special principle of relativity, i.e. that there is no preferred frame of reference.

P.S. On a somewhat less unhelpful note, the simple answer nowadays is that we define it that way. Since the early 1980's the speed of light has been defined to be exactly 299,792,458 m/s. The speed of light is finite and constant for the same reason $\pi$ is finite and constant. :tongue2:

3. Aug 26, 2011

### AgentPancake

hmmm, its like something made the laws of pi and the speed of light etc

4. Aug 26, 2011

### Hurkyl

Staff Emeritus
Aside: "countable" is a measure of cardinality, and thus little to no relation to notions of magnitude or other geometric measure, or to the extended real number $+\infty$.

5. Aug 26, 2011

### Staff: Mentor

Nope. It doesn't seem like that at all from the observation that constants exist. Also, the OP has been answered well all ready but I'll just add that the question is worded poorly, any number is countable. The question is really "why isn't light infinite".