>>12671986Light is composed of photons which are massless propagators, even in a vacuum. In principle, nothing is special about light. If another particle is massless (e.g. gluons), then they should also set the maximum speed limit of the universe. However, gluons cannot propagate in a vacuum, nor can they travel infinite range.
Photons, to our knowledge, are the only particles that satisfy all three of the following:
>Are massless>Can propagate in a vacuum>Have infinite rangeName another particle with these properties, and then we can talk about generalizing the statement. As of now, it seems to be a property unique to photons, and hence the speed of light is special.