Scientists at the University of Cambridge have proposed a new type of money that help them in making decisions based on information arriving at different locations and times. What’s more, this new type of money could also protect against attacks from quantum computers.
Dubbed as ‘S-money’ this new type of money is designed for high-value fast transactions on networks with relativistic or other trusted signaling constraints, defined by inputs that in general are made at many network points, some or all of which may be space-like separated. In fact, it could conceivably make it possible to conduct commerce across the Solar System and beyond, without long time lags, although commerce on a galactic scale is a fanciful notion at this point.
Professor Adrian Kent, from Cambridge’s Department of Applied Mathematics and Theoretical Physics said, “It’s a slightly different way of thinking about money: instead of something that we hold in our hands or in our bank accounts, money could be thought of as something that you need to get to a certain point in space and time, in response to data that’s coming from lots of other points in space and time.”
Considering it as virtual tokens for various transactions, the S- money can respond flexibly in real time across the globe. In addition, it allows users to respond to events faster than familiar types of money, both physical and digital, which follow definite paths through space.
The tokens can be safely exchanged without postponements for cross-checking or verification over the network while wiping out any risk of double-trading. One method for ensuring this uses the intensity of the quantum hypothesis, the physics of the subatomic world that Einstein broadly expelled as spooky.
The need to maintain information privacy is applicable by protocols such as bit commitment, which is a mathematical version of a securely sealed envelope. Data transferred between users in encrypted format once sent and can only be revealed after decryption.
Other scientists have come up with theoretical frameworks for ‘quantum’ money, which is based on the strange behavior of particles at the subatomic scale. Using quantum money for a real-world transaction may be possible someday, but currently, it is impossible to keep quantum money secure for any appreciable length of time.
Kent said, “Quantum money, insofar as it’s currently understood, would require long-term storage of quantum states, or quantum memory. This would require an awful lot of resources, and even if it becomes technologically feasible, it may be incredibly expensive.”
While the S-money system requires large computational overhead, it may be feasible with current computer technology. Later this year, Kent and his colleagues hope to conduct some proof-of-concept testing working with the Quantum Communications Hub, of which the University of Cambridge is a partner institution. They hope to understand how fast S-money can be issued and spent on a network using off-the-shelf technologies.
Kent said, “We’re trying to understand the practicalities and understand the advantages and disadvantages.”
Details are published in the Proceedings of the Royal Society A.