Quantum computing poses new risks for the financial system by undermining traditional cryptography — but it can also enable impossible-to-counterfeit quantum money.
While today’s digital money is a product of the first quantum revolution of the early 20th century, it is the second quantum revolution of the late 20th century that poses its greatest challenge. This second revolution involves a deeper harnessing of quantum phenomena in ways that go far beyond the initial revolution’s focus on understanding and utilizing individual quantum particles.
This is thrilling news for science and technology, but troubling for classical cryptography and, by extension, digital money. Most modern cryptographic systems, such as those securing online banking and cryptocurrencies, rely on the assumption that certain mathematical problems — like factoring large integers or solving discrete logarithms — are computationally infeasible to solve in a reasonable amount of time, even when using very powerful classical computers. But for quantum computers, several of these ”hard” problems become tractable.
In the 1960s, while still a graduate student in physics at Columbia University, Stephen Wiesner proposed a groundbreaking idea: secure money based on the principles of quantum mechanics. His concept, known as quantum money, envisioned each bill being tied to a unique quantum state. The central innovation was that quantum money would be impossible to counterfeit, not just due to technological limits but because of the fundamental laws of quantum physics — entirely independent of any future advances in computing or mathematics.
Although the paper in which Wiesner explained his idea was rejected for publication — likely because it was so ahead of its time that editors and referees could not grasp its significance — it circulated among physicists interested in information theory. It would go on to have a profound impact on the development of quantum cryptography and quantum computing.
You can read my full article at the following link: DuckBucks: Future of Finance, June 2025