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Why is the speed of light arbitrarily the limit? [duplicate]

I know Einstein was great and all. Why is it that exactly at the speed of light is where infinite energy is required to accelerate any object with mass? Is it simply because the math of relativity ...
2k views

What's so special about the speed of light? [duplicate]

What's so special about the speed of light? Why do many equations in physics include the speed of light in vacuum $c$? Why do so many thing depend upon it? Why can't it be the speed of sound? ...
678 views

Why is light in vacuum so slow? [duplicate]

Accepting the speed of light in vacuum and infinite mass and all that, I wonder why light does not have infinite speed? I know light does not have rest mass, but people use the term infinite mass ...
2k views

Why does light travel at finite speed? [duplicate]

We have known for quite some time now that light travels at a finite speed of 3x10^8m/s (approx) through vacuum. But why is that? Why can't the speed be infinite? Or at least higher than the current ...
103 views

Does spacetime have a “preferred” speed/metric? [duplicate]

I read recently that spacetime has a preferred speed, c, and that all observers would agree on the speed of anything moving at c. In particular, there is nothing unique about light when talking about ...
102 views

Universal speed limit [duplicate]

Is there any reason the universe has matter not being able to exceed the speed of light, or why there is a speed limit in the first place? I know why it can't, meaning the basic physics of it. I am ...
83 views

$E=mc^2$ what is unique about the speed of light? [duplicate]

What unique property of light, makes it the conversion factor between energy and mass? It has to be more than a coincidence that the speed of light, just happens to be the correct number number to ...
42 views

This question has been nagging me for sometimes now, and even after studying all those relativity still cannot find an appreciable answer. The speed of light is $c$ defined and measured as constant $... 8answers 9k views Why does the speed of light in vacuum have no uncertainty? I could understand that the definition of a second wouldn't have an uncertainty when related to the transition of the Cs atom, so it doesn't have an error because it's an absolute reference and we ... 17answers 3k views The origin of the value of speed of light in vacuum Meaning, why is it the exact number that it is? Why not 2x10^8 m/s instead of 3? Does it have something to do with the mass, size or behavior of a photon? To be clear, I'm not asking "how we ... 9answers 2k views Would it be possible to develop special relativity without knowing about light? My understanding of special relativity is that it is fundamentally based on the constancy of the speed of electromagnetic radiation - that this speed is a physical law (or derivable from physical laws ... 3answers 1k views The reference frame of$c\$

I don't have a lot of knowledge of special relativity and associated topics; some of the few things I know are that "all motion is relative" (that is, there is no 'stationary reference frame'), and ...
2k views

Speed of light definition

I understand the speed of light to be an EXACT number. If permeability of free space has a factor of pi in it, how can this be?