Einstein’s famous equation, E=mc2, taught us that matter can be turned into energy. This happens naturally in the universe, although we've also mastered it in places like nuclear reactors. The equation also tells us that the opposite is true. It should be possible to create matter out of energy, and that's exactly what scientists at Imperial College London are trying to do.
The team, led by Professor Steven Rose, are trying to achieve their goal by making two powerful lasers – one with 1,000 times and the other with 1 million times the energy of visible light – hit the same target chamber simultaneously. The approach is based on the Breit-Wheeler process, first put forward in 1934, which showed that in theory, you can get an electron and a positron (its antimatter twin) out of two colliding photons.
So far, nobody has been able to recreate this, and people have started adding other energy particles to try to make it happen. But in 2014, Professor Rose proposed a method to create the Breit-Wheeler process without the involvement of any other particles. This is the approach that is currently being tested.
“This would be a pure demonstration of Einstein’s famous equation that relates energy and mass: E=mc2, which tells us how much energy is produced when matter is turned to energy," Professor Rose said in a statement. "What we are doing is the same but backwards: turning photon energy into mass, i.e. m=E/c2.”
This is not the only team working hard to try to “break the vacuum” and get matter out of energy. Several groups are attempting different approaches, even employing brute force by using the most powerful lasers ever designed. This uses a more sophisticated optical setup to make the Breit-Wheeler process happen.
“When Gregory Breit and John Wheeler first proposed the mechanism in 1934, they used the then new theory of the interaction between light and matter known as quantum electrodynamics (QED)," Dr Stuart Mangles, who co-leads the team, added. "Whereas every other fundamental prediction of QED has since been demonstrated experimentally, the ‘two-photon Breit-Wheeler process’ has never been seen.”
Creating matter from energy is not simply a box-ticking exercise. It can lead to a better understanding of several high-energy astrophysical processes.
“If we can demonstrate it now, we would be recreating a process that was important in the first 100 seconds of the universe and that is also seen in gamma ray bursts, which are the biggest explosions in the universe and one of physics’ greatest unsolved mysteries,” Dr Mangles concluded.
