The Quantum Threat to Bitcoin: How a Powerful Computer Can Steal Your Cryptocurrency in Under 10 Minutes

The security of bitcoin relies on complex mathematical equations that are difficult for classical computers to solve, but quantum computers can potentially crack these codes. The elliptic curve cryptography used by bitcoin is based on a one-way function, where it is easy to generate a public key from a private key, but virtually impossible to do the reverse. However, quantum computers can use Shor's algorithm to break this one-way function, allowing them to derive the private key from the public key and gain control of the associated bitcoin. Google's recent research has shown that the number of qubits required to run Shor's algorithm against bitcoin's elliptic curve is significantly lower than previously thought, making it more feasible for a large-scale attack. If a quantum computer can derive a private key within a short time frame, such as the estimated nine minutes, it could potentially steal bitcoin from vulnerable wallets. The main concern is the 6.9 million bitcoin that have already had their public keys exposed on the blockchain, making them susceptible to an 'at-rest' attack. This article will be followed by a final piece that discusses the practical implications of this quantum threat and what it means for the future of bitcoin.