- Theory of turning light into matter first thought of in 1934 by two physicist
- Researchers at Imperial College London now believe they can do it
- Process would involve using newly available high-powered lasers
- Matter created would be subatomic particles not visible to naked eye
Scientists have found out how to turn pure light into matter for the very first time – after 80 years of trying.
The idea was first dreamt up in 1934 by two physicists, but they never expected anybody to be able to physically demonstrate their prediction.
But researchers at Imperial College London say they have found a way to convert light into matter by using new equipment in the form of an extremely powerful high-intensity laser, capable of speeding up electrons to just below the speed of light.
The 80-year-old theory involved smashing together two particles of light, or photons, to create an electron and a positron – subatomic particles found in all materials.
Although scientists at the university believe they can create matter, at this stage the end result would not be visible to the naked eye.
Professor Steve Rose, from imperial College, said: ‘What was so surprising to us was the discovery of how we can create matter directly from light using the technology that we have today in the UK.
‘As we are theorists we are now talking to others who can use our ideas to undertake this landmark experiment.’
The experiment would involve blasting electrons, sped up by lasers to just below the speed of light, into a slab of gold to create a beam of photons a billion times more energetic than visible light.
The next stage would need a tiny gold can called a hohlraum, German for ’empty room’.
Scientists would fire a high-energy laser at the inner surface of this to create a thermal radiation field, generating light similar to that emitted by stars.
They would then direct the photon beam from the first stage of the experiment through the centre of the can, causing the photons from the two sources to collide and form electrons and positrons.
It would then be possible to detect the formation of the electrons and positrons when they exited the can – in their microscopic state.
Oliver Pike, who is currently completing his PhD in plasma physics at Imperial College London, said: ‘Although the theory is conceptually simple, it has been very difficult to verify experimentally. The experimental design we propose can be carried out with relative ease and with existing technology.
‘Within a few hours of looking for applications of hohlraums outside their traditional role in fusion energy research, we were astonished to find they provided the perfect conditions for creating a photon collider.
‘The race to carry out and complete the experiment is on.’
The research published in Nature Photonics shows how the original theory, put forward by US physicists, Gregory Breit and John Wheeler in the 1930s, could be proven in practice.
This ‘photon-photon collider’, which would convert light directly into matter using technology that is already available, would be a new type of high-energy physics experiment.
The experiment would recreate 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.