Month: August 2017

There's a great moment in The Hobbit when Bilbo Baggins is exploring a stinking troll cave and finds an ancient Elven short sword, lost for centuries, buried under the muck. It’s Sting, baby. And nobody wonders whether Sting will be less powerful than all the flashy new swords on the market. They assume that it’s more powerful.

In some of the most engrossing worlds ever imagined—Star Wars, The Hobbit, and even Dune—the older something is, the better. The characters in those stories respect the achievements of their long-disappeared ancestors, and they honor the technological feats of heroes whose deeds have turned to legend.

Maybe we’re drawn to these stories because they’re so different from our own society, where we’re obsessed with the latest, freshest version of any gadget—and it’s off to the trash heap with whatever falls out of date. If Bilbo had found an iPhone in that cave, I highly doubt it would have been worth wielding for the rest of his adventure and then passed down through his family.

Enlarge (credit: Christopher Gutiérrez, Daniel Walkup/NIST)

Quantum mechanics comes with something called the uncertainty principle. This states that there are pairs of properties that cannot be simultaneously known to arbitrary precision. This is not due to the way a measurement changes the properties of what it measures. Instead, it is due to how quantum mechanics forces us to make measurements.

The uncertainty principle was once something that was discussed as, well, something that would only cause problems in principle. But since the 1980s, physicists have been making measurements that bump up against the uncertainty principle. These were once time-consuming and difficult measurements that only a few labs could do. Two decades later, and we are contemplating mass production of sensors that are going to be limited by the uncertainty principle.

Avoiding the uncertainty principle is now a cottage industry in physics. The way to go about it is to more carefully examine the sort of measurement you want to make. For instance, the position and momentum of an oscillator are bound by the uncertainty principle. But the relative position and momentum of two oscillators is not. By ensuring that your measurement device depends on that relative measurement, you can gain a substantial advantage, according to a group of international researchers who recently published in Nature.