The rise of quantum computing has been deemed a credible threat to Bitcoin and the broader cryptocurrency landscape by Wall Street broker Bernstein, albeit one that can be effectively managed. Recent breakthroughs in the field have accelerated the timeline for potential attacks on modern cryptography, shifting the risk from a distant concern to a more immediate, yet still medium to long-term, issue. Analysts, led by Gautam Chhugani, emphasized that the advent of quantum computing should be viewed as a system upgrade cycle rather than an existential threat.
The unique properties of quantum computing, including superposition and entanglement, enable it to solve complex problems more efficiently than classical computers, potentially weakening cryptographic systems like elliptic curve encryption. However, the report noted that the threat is not unique to Bitcoin and spans multiple industries, from finance to defense. Bernstein highlighted that the exposure is primarily concentrated in older, 'legacy' wallets, holding approximately 1.7 million BTC, while newer practices and protocols reduce vulnerability.
The broker also stated that Bitcoin mining, which relies on SHA-based hashing, remains secure even in advanced quantum scenarios. With an expected transition period of three to five years, the crypto industry is anticipated to have sufficient time to adapt to post-quantum cryptography, implementing upgrades such as new wallet standards, reduced address reuse, and key rotation. A recent academic paper further underscored the enormity of the task, suggesting that a quantum attack on the Bitcoin blockchain would require an energy output comparable to that of a star.