atomic clock primary subject, 16 assertions
Subgroups 1
accurate atomic clock 1
Aspects 0
AtLocation 3
metrology institutes 0.25
observatory 0.25
more than 30 countries 0.25
CapableOf 5
keep time 0.71
use an electron transit… 0.46
cool atom 0.43
interact with dark matt… 0.25
pave the way 0.16
HasProperty 2
accurate 0.59
stable 0.42
IsA 2
a clock device 0.57
the most accurate clocks 0.16
ReceivesAction 4
invented 0.61
used in many scientific… 0.25
used to control the wave 0.16
detailed in paper 0.16