Timeline for Why is the speed of light said to be constant when we know it slows down in a medium?
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jan 6, 2017 at 16:21 | comment | added | John Duffield | @ACuriousMind : we do use the motion of light to define the second. It's "the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom". You effectively sit there counting microwaves going by, and when you get to nine billion, you jump up and say that's a second. The answer you refer to demonstrates a lack of understanding of the tautology pointed out by Magueijo and Moffat. If you doubt me on this ask a question and I'll answer it in detail. | |
| Jan 6, 2017 at 15:16 | comment | added | ACuriousMind♦ | We do not use the motion of light to define the second, and this answer fails to distinguish between the local speed of light and the coordinate speed of distant light. The former is constant, the latter is not, see also e.g. this answer. | |
| Jan 5, 2017 at 13:15 | comment | added | John Duffield | @Bill Alsept : I don't know Bill. Perhaps you should ask in the chatroom? | |
| Jan 4, 2017 at 18:00 | comment | added | Bill Alsept | John, I agree with your answer about The light bending back-and-forth between the atoms and thus taking a longer path. I posted that earlier but someone erased my previous comments. I'm not sure why? | |
| Jan 4, 2017 at 17:13 | history | answered | John Duffield | CC BY-SA 3.0 |