Nugatory
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When we're talking about the speed of light being the same everywhere, we mean locally: we measure the speed of light inside our lab, and our lab is small enough that curvature effects are negligible across its width. No matter where in the universe we position our lab, as long as it is small enough we will get the same result when we measure the speed of light.Rick16 said:How can the speed of light have the constant value -- suposedly everywhere in the universe -- of 300,000 km/s and at the same time be ill defined?
When we say that the speed of light is ill-defined in curved space, we mean globally: there is no sensible definition of the speed when the curvature effects are not negligible.