Wall Street remains divided over the readiness of quantum computing for practical financial applications, while new research from Google has sharply reduced the estimated number of qubits needed to threaten Bitcoin's cryptographic security.
Goldman Sachs (GS) conducted a test three years ago, partnering with Amazon (AMZN) to determine if quantum computing could enhance portfolio returns for wealthy clients. The results were disappointing: the algorithm would have required millions of years to complete the task, and the computer would need at least 8 million logical qubits. Current systems still operate with fewer than 100 qubits. Goldman later disbanded most of its quantum team during a cost-cutting initiative.
In contrast, JPMorgan Chase (JPM) maintains a team of over 50 physicists, computer scientists, and mathematicians working on optimization, machine learning, and cryptography. Some analysts believe quantum computing could become the next major computing trade after artificial intelligence, though others remain cautious about investing in a technology with limited real-world utility.
Xanadu Quantum Technologies emerged as a notable market story this week. Founder Christian Weedbrook became a billionaire within six days of the company's public listing, with his stake valued at approximately $1.5 billion. Xanadu shares closed at $31.41 on Friday, up 251% for the week. The company plans to build one of the first quantum data centers by 2030, using photons transmitted through fiber-optic links.
Meanwhile, Nvidia (NVDA), the world's most valuable company, released open-source artificial intelligence models on Tuesday to support quantum computing research.
Bitcoin's Quantum Threat Reassessed
Peter Shor's 1994 algorithm demonstrated that a sufficiently powerful quantum computer could break the elliptic-curve cryptography underpinning Bitcoin. Previous estimates suggested millions of physical qubits would be needed, but a recent Google (GOOGL, GOOG) investigative report reduced that threshold to fewer than 500,000 qubits.
The report outlines a more direct attack path. Part of Shor's algorithm depends only on fixed elliptic-curve data, which is public and identical for every Bitcoin wallet. A future quantum machine could perform that stage in advance and remain in a ready state. Once a public key appears—either in the mempool during a transaction or on-chain from a previous spend—the machine would need only to complete the second stage, which Google estimates would take about nine minutes. Since Bitcoin's average block time is ten minutes, an attacker would have a 41% probability window to calculate the private key and submit a competing transaction redirecting the funds.
A larger concern involves the 6.9 million bitcoin—roughly one-third of the total supply—held in wallets where the public key has already been exposed permanently. These coins face an at-rest attack, meaning they could be targeted at any time once a sufficiently powerful quantum computer becomes operational.
