Imagine a world where you can find out exactly what lies under your feet, get advanced warning of volcanic eruptions, look around corners or into rooms, and detect initial signs of multiple sclerosis.
Welcome to quantum sensing, a technology that could transform our world.
At their heart, these sensors rely on the often baffling behaviour of subatomic particles, where the classical assumptions of Newtonian physics cease to exist.
“Quantum physics is said to be ‘spooky’, with particles being in two places at once, but it might be less spooky if you think of them as waves – and waves can be in several places at once,” says Prof Kai Bongs of Birmingham University.
Prof Bongs’ Birmingham team is part of a consortium of academics and businesses developing quantum gravity sensors or gravimeters that will be twice as sensitive and 10 times as fast as current equipment.
This project, labelled Gravity Pioneer, could greatly simplify how engineers and surveyors plan and execute major construction projects.
Currently, the only way to find out what is underneath the ground is often to carry out exploratory digging, which is both time-consuming and expensive.
“Some have said that what lies below one metre under the streets of London is less well-known than Antarctica,” says Prof Bongs.
This is a major headache for construction companies who have to carry out surveys that can take days.
“There are thousands of mine shafts in the UK, often two metres or less across, and if the top of the shaft is five metres or more below ground then they can’t currently be detected,” explains George Tuckwell of engineering services firm RSK, which is leading the Gravity Pioneer project.
“But the new sensor will be able to see most of them.”
It uses rubidium atoms cooled by lasers to just above absolute zero (-273C) that are propelled upward in a vacuum and then measured as they fall back under gravity.
It is so sensitive it can detect the tiny fluctuations in gravity that result from such relatively small underground structures.
This should help speed up survey times, says engineering firm Teledyne e2V, which is turning Birmingham’s prototype into a commercial model.