The provided text offers a comprehensive analysis of the existential threat quantum computing poses to Bitcoin's security, primarily focusing on two algorithms: Shor's and Grover's. It explains how Shor's algorithmcould break Bitcoin's foundational ECDSA cryptography, leading to direct theft of funds, while Grover's algorithm could impact mining and network consensus. The document then examines the highly uncertain timelines for cryptographically relevant quantum computers, emphasizing the strategic dilemma this presents for a decentralized network requiring long lead times for upgrades. It quantifies the substantial financial riskto existing Bitcoin, particularly from legacy addresses, and discusses the Post-Quantum Cryptography (PQC) solutions being standardized by NIST, outlining the significant technical and social challengesinvolved in upgrading Bitcoin's protocol and migrating user funds.