Quantum Memory Looms: Breaker and Replacer of Bitcoin

A device that could break Bitcoin and replace it is still in development, according to Stefano Gogioso, an Oxford lecturer. He argues that quantum memory will decide whether Bitcoin breaks or gets replaced by something better.

Gogioso says the promise of quantum cryptography now rests on building a single piece of hardware: portable long-term quantum memory. These devices would power an entirely new class of applications, such as quantum money, which is the ultimate incarnation of a digital store of value.

The bottleneck in developing quantum money has been that nobody can hold the states for long. The best laboratory systems keep one alive for seconds, which is why the case for quantum money has stayed theoretical. Gogioso's design requires stability measured in months or ideally forever, portability, and capacity running to billions of separate states.

Gogioso argues that a fault-tolerant quantum computer must keep fragile states alive at scale against noise for as long as a calculation runs. Remove the computing, and a quantum memory device is what remains. Denying one therefore means denying the other.