Why is quantum computing seen as a challenge to Bitcoin? - Investing.com

Quantum computing threatens Bitcoin’s cryptographic foundation by potentially breaking its ECDSA signature scheme, which secures transactions and wallets. Experts warn large-scale quantum computers could reverse-engineer private keys from public addresses. The Bitcoin Policy Institute reports rapid quantum advancements are accelerating the timeline for necessary network upgrades. Previous estimates of a 10–30-year window may now shrink to under a decade due to unexpected breakthroughs in error correction and qubit stability. Cybersecurity researchers emphasize "harvest now, decrypt later" risks, where encrypted Bitcoin data could be stored today and cracked once quantum-capable machines emerge. This undermines long-term trust in blockchain immutability. Industry responses include proposals for post-quantum cryptography (PQC) like hash-based signatures or lattice-based algorithms. However, implementing upgrades requires consensus among developers, miners, and node operators, complicating timely adoption. Analysts urge proactive testing of quantum-resistant solutions, citing delays in standardization and deployment as critical vulnerabilities. Without preemptive action, Bitcoin’s $1T+ market cap could face existential security threats by the 2030s.