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What’s an attosecond?

As I continue to ponder the mind boggling character of quantum physics (the 10^-n reality), I’m fascinated by articles about novel experiments which routinely explore infinitesimal time scales and distances. Nanoscale (10^-9) is amazing! But now there’s the attosecond.

This article (April 30, 2018), “The ‘Attoclock’ Shows How Fast Electrons Move in a Millionth of a Billionth of a Second,” introduces the 10^-18 time slice, molecular movies, and an experimental attoclock.

… it takes a few hundred attoseconds for a tiny electron to move from one side of an atom to the other during a chemical reaction.

… in order to understand the invisible universe of quantum events occurring all around us, scientists need a way to measure molecular action at that attosecond scale. According to a new paper published in the March issue of the journal Nature Photonics, a team of scientists has figured out a new way to do just that, with a new “attoclock” that keeps time to a mind-bogglingly tiny time scale. [Video: How to Build the Most Accurate Atomic Clocks]

The SLAC Laboratory is home to some of the fastest X-ray lasers in the world, capable of firing pulses that last just a few dozen attoseconds apiece. When directed at individual atoms and molecules, flashes that fast can essentially make what SLAC calls “molecular movies” — a series of pictures taken on the attosecond timescale, capturing chemistry in motion.

But one problem with photographing quantum-physics events is that, until now, there wasn’t a very reliable way of measuring how fast or how powerful those ultrafast X-ray blasts really were — and without precise measurements, scientists couldn’t interpret the data they collected from these molecular movies.

Holy femtoseconds, Batman!