⛏️ Bitcoin: quantum attack on mining would require the energy of a star Two new academic studies offer a far more sober picture of quantum threats to Bitcoin than the alarmist headlines that periodically rattle crypto markets. The first, by Pierre-Luc Dallaire-Demers and the team at BTQ Technologies, finds that at January 2025 mining difficulty, a fleet of quantum miners running Grover's algorithm against SHA-256 would require approximately 10²³ qubits consuming 10²⁵ watts of energy — roughly 3% of the Sun's total energy output. For reference, the entire Bitcoin network currently consumes around 15 gigawatts. A quantum 51% attack, the researchers conclude, is not merely expensive — it is physically unfeasible at any scale a real civilization could power. The second paper, by Peter Gutmann of the University of Auckland and Stephan Neuhaus of the Zürcher Hochschule, takes a satirical approach to a serious point: the authors replicated every major quantum factorization "breakthrough" of the past twenty years using a 1981 VIC-20 home computer, an abacus, and a dog named Scribble trained to bark three times. Their analysis shows that nearly all such demonstrations relied on numbers with prime factors easily identified through a classical trick dating to John von Neumann in 1945, or offloaded the hard computation to classical hardware before passing a simplified version to the quantum device. https://t.co/KIJBmJxwFL