The dream of a completely secure, impenetrable and completely private digital payment system could soon be realized thanks to new research from the University of Vienna.
in paper published A team of researchers at the Vienna Center for Quantum Science and Technology presented on July 4 titled “Quantum Digital Payments Showcase” what may be the first “unconditionally secure” digital transaction system based on quantum mechanics.
To achieve this, the researchers encrypted a payment transaction using a pair of entangled quantum photons. Through this entanglement, where any change in the characteristic state of one photon is exactly reflected in the other, even when separated by a distance, the researchers were able to ensure that any attempts to modify the transaction would be thwarted by the very nature of quantum mechanics. .
According to the researchers’ paper:
“We show how quantum light can secure everyday digital payments by creating inherently tamper-proof quantum cryptography.”
One of the most useful features of quantum entanglement is the fact that we can’t know what state an entangled object is in until we measure it.
A simple way to understand quantum mechanics and measurements is to imagine flipping a coin and then catching it and covering it with your hand before you or anyone else can see which side it landed on. Until you raise your hand, they can be heads or tails with equal probability. Once measured, the uncertainty collapses and you have the measurement.
Scientists can exploit this by using entangled objects, such as photons, to ensure parity and to transmit information that cannot be modified or intercepted.
Related topics: The History of Computing: From Abacus to Quantum Computers
Thus, the researchers generated entangled photons using the laser process and encoded them with transactional information. The photons were then sent through more than 400 meters of fiber optic cables to successfully complete a digital payment transaction between parties in different buildings.
If the bad actor attempts a hostile attack on such a transaction, the quantum state of the photons will collapse due to the measurement, and the system will generate a new pair of photons entangled with a new, non-forgeable cipher.
While this could represent a breakthrough in quantum communication for digital payments, there is one small caveat: Currently, researchers say a simple digital payment takes “dozens of minutes” to complete using the method.
However, this limitation may only be temporary, as the researchers insist that this is not a hard stop due to the laws of physics but only a slight technological limitation – one that can be resolved by high-intensity photons.
“Indeed, brighter sources of entangled pairs of photons have already been demonstrated, which can reduce the transmission time of a quantum code to less than a second,” the authors wrote.
