Time’s up for ‘leap second’
Summary
Host David McCullagh discusses the decision to abolish the leap second with physicist Dr. Shane Bergen from University College Dublin. They explain how Earth's rotation is speeding up due to shifts in the liquid iron mantle, creating a mismatch between astronomical time and atomic clocks. The conversation covers the historical context of timekeeping, the technical chaos caused by previous leap seconds, and the future implication of a potential "leap hour."
Topics discussed
Introduction: Earth's rotation speeding up and leap second abolition
Dr. Shane Bergen explains the history of the leap second
How the Moon slows Earth's rotation and the mismatch in time units
Impact of leap seconds on computer systems and past glitches
Discussion on Y2K and the fragility of modern technology
The need for precise time synchronization in global networks
International treaty to stop leap seconds and future leap hours
Why Earth's rotation is accelerating: liquid core movement
Natural phenomena vs. human-invented time systems
Time as a human construct: Egyptian and Babylonian origins
Relativity of time and Einstein's work; closing remarks
Listen ad-free on Castria