> ( ) civil time and solar time have to remain in synch to better than a second
No, they don't. Proof of this is that they already aren't: there is a band no more than 15 arcseconds wide in each timezone where it is true, and everywhere outside that, civil time does not correspond to solar time.
No, they don't. Proof of this is that they already aren't: there is a band no more than 15 arcseconds wide in each timezone where it is true, and everywhere outside that, civil time does not correspond to solar time.