Can light exist without spacetime?

Since the medium in which light propagates is spacetime, would light be able to exist if spacetime did not exist? Is this like one of those chicken/egg problems, or can light be thought of as a legitimately independent entity? This might be bordering on an philosophical question, so if it is, let me know and I'll delete it.

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Its a difficult question as I can't imagine "something" without space and time. –  orion Aug 15 '13 at 16:43

@JoelB Actually the limiting quantity $c$ is not, from a fundamental standpoint, meant to be understood as the speed of light, but a (initially free, when deciding how to build a universe!) parameter of a class of transformations that respect very basic symmetries. It comes from that to mean the speed of a massless particle, which light just "happens" to be. If light were found to have a tiny mass, this would not affect our definition of $c$ (although it would be a sharp headache for the SI committee!). See physics.stackexchange.com/a/71226/26076 –  WetSavannaAnimal aka Rod Vance Aug 16 '13 at 2:57