You might find this paper interesting: A Derivation of Special Relativity
from Causal Sets--http://arxiv.org/abs/1005.4172
It doesn't answer why c is the value of c, but it's an interesting way to show that there must be an invariant bounding speed limit. It doesn't assume the "existence of space
or time, motion, constancy of the speed of light, or the principle of relativity."
It doesn't answer why c is the value of c, but it's an interesting way to show that there must be an invariant bounding speed limit. It doesn't assume the "existence of space or time, motion, constancy of the speed of light, or the principle of relativity."