Picosecond - Wikipedia

A picosecond is an SI unit of time equal to 10−12 or 1/1,000,000,000,000 (one trillionth) of a second. That is one trillionth, or one millionth of one millionth of a second, or 0.000 000 000 001 seconds. two hyperfine levels of the ground state of the caesium-133 atom at absolute zero; 330 picoseconds (approximately) – the