- #1
Bob Enyart
- 15
- 0
- TL;DR Summary
- ESC is always defined for the one-way speed of light in a vacuum. So is Einstein's Synchrony Convention needed also for light travelling only within Earth's atmosphere (where it travels more slowly, apparently at about 99.9% c)?
Einstein's synchrony convention (ESC) defines the one-way speed of light as equal to the roundtrip speed IN A VACUUM, at least, the discussions and papers I read on it (even Einstein's 1905 paper) always seem to set the context as in space (a near vacuum) or in a (theoretical) vacuum. I'm wondering then if the ESC is needed for a light transmission starting and ending and traveling only within Earth's atmosphere? If the stat I looked up is accurate, it appears that light travels in a vacuum only three hundreths of 1% faster than it travels through air. So, do you think ESC is needed also in Earth's atmosphere, or might there theoretically be a way to measure its one-way speed because it's not traveling as fast as in a (near) vacuum. (Sorry if this question isn't worded as well as it should be.)