No answer can be given to this question, it is one of the axioms of relativity theory. The explanation is trying to explain the axiom in terms of the theory bui

No answer can be given to this question, it is one of the axioms of relativity theory. The explanation is trying to explain the axiom in terms of the theory built on it. I found these answers to be more informative: http://physics.stackexchange.com/questions/2230/why-and-how-is-the-speed-of-light-constant http://physics.stackexchange.com/questions/2230/why-and-how-...