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## Why The Speed of Light is Finite

I do wonder why the speed of light is 299 792 458 m/s instead of 400 000 000 m/s or 50 billion m/s.  I know it’s constant and like other constants the universe just sort of has them and299 792 458 m / s whether they are this value or that value, the point is, they have a constant value.299 792 458 m / s.

It’s still fun to think about.

Here are two decent resources explaining the situation with the finiteness and constance of the speed of light.

Why is the speed of light constant

Many novel ideas are found on the Internet. One not so novel notion is that Einstein was wrong and that the “lightspeed limit” is really just some international conspiracy of conservative “establishment” scientists. Those who make this point neglect the fact, however, that the deduction about the speed of light is not a result of some exotic assumptions or blind speculation, but a fairly simple consequence of some fundamental assumptions about nature: in other words, if you wish to prove that Einstein was wrong, you have to show that either elementary logic is incorrect, or that some of our basic assumptions about nature are outright false.

Here is why.

Why isn’t the speed of light infinite

The fact that space and time must get mixed up to keep the speed of light constant implies that, in some sense, space and time must be the same, despite our habit of measuring space in meters and time in seconds. But if time and space are similar to the extent that they can be converted one into the other, then one needs some quantity to convert the units–namely, something measured in meters per second that can be used to multiply seconds of time to get meters of space. That something, the universal conversion factor, is the speed of light. The reason that it is limited is simply the fact that a finite amount of space is equivalent to a finite amount of time.