No leap second for December 31, 2020

World timekeepers have decreed there will be no leap second on December 31, 2020. Source: https://earthsky.org/human-world/leap-second-june-30-december-31-why-need-controversy…

New type of atomic clock could help scientists detect dark matter and study gravity’s effect on time

Atomic clocks are the most precise timekeepers in the world. These exquisite instruments use lasers to measure the vibrations of atoms, which oscillate at a constant frequency, like many microscopic pendulums swinging in sync. The best atomic clocks in the world keep time with such precision that, if they had been running since the beginning of the universe, they would only…

JILA’s novel atomic clock design offers ‘tweezer’ control

JILA physicists have demonstrated a novel atomic clock design that combines near-continuous operation with strong signals and high stability, features not previously found together in a single type of next-generation atomic clock. The new clock, which uses laser “tweezers” to trap, control and isolate the atoms, also offers unique possibilities for enhancing clock performance using the tricks of quantum physics. …