Abstract

Circa year 2000: a) One second is duration of 9,192,631,770 microwaves from caesium-133; b) Paris atomic clock sync. signals are isotropic wrt Non-Rotating Earth-Centred Frame; c) Clock rates slowed by speed wrt the NRECF, and increased by remoteness from Earth centre; d) To maintain synchronization, clocks higher than Paris are biased to run slower. Circa year 3000: a) Master clock in orbit on other side of Sun; b) 'Arcadia ' sync. signals are isotropic wrt the Sun-Centred Frame; c) Clock rates are slowed by speed wrt SCF, and increased by remoteness from the Sun; d) To maintain synchronization, the Paris clock is biased to run faster to compensate for Earth gravity, and biased cyclically to run slower at noon and faster at midnight to compensate for Earth spin. Circa year 4000: a) Master clock at cosmic rest (370 km/s in the direction of Aquarius); b) 'Elysium' sync. signals are isotropic wrt the Cosmic Background Radiation Frame; c) Clock rates are slowed by speed wrt the CBRF, and increased by remoteness from Milky Way center; d) To maintain synchronization, the Paris clock is biased to run faster to compensate for Sun gravity, and biased cyclically to run slower in June and faster in December to compensate for Earth's orbital speed.