Scientists like to think that true measures of our understanding are our ability to predict something, and, in experimental physics, control something. This year’s Nobel Prize in physics has been awarded to Serge Haroche and David Wineland for controlling the quantum world in ways that, not so long ago, were simply unthinkable. When I say “controlling the quantum world,” I mean controlling not just the physical motion of a single atom, but also the internal state of the atom. It is the difference between being able to set off an avalanche, and being able to control where every snowflake goes once the avalanche is in motion.
This level of precise control allows us to use the internal states of atoms, ions and photons as information carriers, similar to bits in today’s computers. That means that certain calculations that have been impossible until now can become a lot easier. Soon, thanks to quantum computing, we’re going to be inventing things we never thought to invent before.
Ultimately, quantum physics research is about the pursuit of control—a pursuit that has a long history. Technology, after all, is at its most base form an attempt to better understand and manipulate nature. The first steam engines, for example, were the products of inspired engineering, based on very little understanding of heat, energy, pressure and temperature. The desire to produce more powerful steam engines with higher efficiencies drove us to research, develop and understand more about this aspect of nature. With that understanding came control, in this case over the thermal behavior of groups of atoms and molecules.
The next revolution, and one that is already upon us, is driven by absolute control of individual electrons, atoms, light particles and ions. This year’s Nobel Prize recognizes the latest achievement in humanity’s attempts to control and predict the natural world. I’ll eschew a deep dive into scientific detail—you can read that kind of thing here—but to understand what Haroche and Wineland have done, picture a swing. Swings have a certain rhythm to them that make them very predictable. But the quantum swings that Haroche and Wineland play with are very delicate, and the slightest passing breeze will disturb them. In short, these swings are, left to their own devices, unpredictable and short lived. That is, a quantum swing, once set in motion, quickly stops again.
Haroche and Wineland have worked on ways to keep their quantum swings in motion. Indeed, not just in motion, but predictable for long periods of time.