When an electron meets its antimatter partner — a positron — they can annihilate, turning into gamma rays. But can you run that process in reverse: running high-energy photons together to make electrons and positrons? Quantum electrodynamics, which is the theory of the interactions of light and matter, says yes. In fact, this sort of process happens in high-energy astronomical systems, but it’s not exactly easy to do in the lab.
A new proposal published this week demonstrated how to turn light into matter in a simpler — and possibly new — way. As I explained in The Daily Beast,
O. J. Pike, F. Mackenroth, E. G. Hill, and S. J. Rose showed that if you send gamma rays into a special heated gold chamber known as a “hohlraum,” the photons would annihilate. (Hohlraum is just the German word for “empty room,” in the typical physics habit of giving fancy-sounding terms to simple concepts.) The result would be hundreds of thousands of pairs of electrons and positrons—and an exciting new way to study the interactions between light and matter. [Read more…]
As a postscript: I’m preparing to head back home after a week at a conference on gravitational waves. Expect to hear more about that sometime in the next few months. (Yup, gonna make you wait.)