Part of A Quest in Honor of Jessica Pierce

Petahertz (PHz) are a unit of frequency, which is to say, the number of times that an event occurs each second. Because of the peta prefix, petahertz measure hertz in the quadrillions, which is to say that 1 PHz is equivalent to 1,000,000,000,000,000 Hz, or 1015 events per second.

Here are some examples of phenomena in the petahertz range.


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