Physicists invent a Back to the Future-style flux capacitor; have no plans to travel back in time
For those with better things to do than re-watch Back to the Future over the bank holiday weekend, the film’s time-travelling DeLorean works because of an entirely fictional piece of technology called a flux capacitor.
We say fictional, but a group of scientists has now proposed a device that uses the quantum tunneling of magnetic flux, around a capacitor, to break time-reversal symmetry. One of the proposed circuits is even modeled on the three-pronged design of the flux capacitor in the 1985 film.
Technically, the research published this week in Physical Review Letters can be called a flux capacitor but don’t expect it to enable time travel. The research could instead be used to create a new generation of electronic circulators – devices that control the direction of movement for microwave signals.
The work is the result of collaboration between the Australian Centre for Engineered Quantum Systems (EQUS) and the Australian Centre for Future Low-Energy Electronics Technologies (FLEET).
“We propose two different possible circuits, one of which resembles the iconic three-pointed-star design of the cinematic flux capacitor,” said FLEET associate investigator professor Jared Cole.
“In it, quantum ‘tubes’ of magnetic flux can move around a central capacitor by a process known as quantum tunneling, where they overcome classically insurmountable obstacles.”
The effect of the circuit’s magnetic fields and electrical charges allow it to break what the physicists call time-reversal symmetry. “Unfortunately this effect does not allow us to actually travel back in time,” noted professor Tom Stace, from the University of Queensland. “Instead, it means that signals circulate around the circuit in only one direction, much like cars on a roundabout.”
It might not be powering a time machine anytime soon, but the new circulator has the potential to be an important part of future technologies, such as for precisely directing signals within quantum computers. In the shorter term, the technology could find itself being used to improve Wi-Fi signals and boost mobile antennas. So it might not make Back to the Future a reality, but it could make it easier for you to stream Back to the Future on the internet. O Brave New World.
Lead image credit: Universal Pictures