Amid renewed focus on the Quantum Computing (QC) threat for crypto encryption algorithms, Google has another update: major digital currencies like Bitcoin and Ethereum are even more vulnerable to Quantum attacks than previously thought. Both networks use Elliptic Curve Cryptography (ECC) based on the Elliptic Curve Discrete Logarithm Problem (ECDLP) for security.
According to a blog post by Google Research titled “Safeguarding cryptocurrency by disclosing quantum vulnerabilities responsibly”, the tech giant predicts that it will require much less QC resources to beat the elliptic cryptographic standards adopted by both Bitcoin and Ethereum. Based on the latest estimate, fewer than 500,000 qubits will be required to compromise large sections of these networks.
The post reads:
“…., We estimate that these circuits can be executed on a superconducting qubit CRQC with fewer than 500,000 physical qubits in a few minutes, given standard assumptions about hardware capabilities that are consistent with some of Google’s flagship quantum processors…, ”
Previous Predictions Were Overestimated – Google
Previously, it was estimated that more than 10 million qubits might be required to circumvent the popular encryption protocol, but Google’s latest update suggests it might need only a fraction of that, raising concerns for the broader crypto market. The report claims that such a powerful computer would be able to break BTC’s encryption standard in just 9 minutes–less than the 10-minute average block creation time.



 To put things into perspective, the latest QC hardware is rated anywhere between 500 and 1000 qubits right now. Google’s top quantum processor, Willow, features 105 superconducting qubits. Further upgrades are designed to be 2,000 times more energy-efficient than traditional supercomputers for specific tasks, and their qubit count is likely to rise over time as well.
Quantum D-Day Drawing Near?
While the current power of quantum computers is still far from compromising the cryptographic security protocols of Bitcoin, Ethereum, and other cryptocurrencies, the latest update is a cause for concern.
Previously, Google estimated that quantum computers could break BTC’s security within 3 years. While the firm’s research division has yet to update the timeline, Quantum D-Day is likely to approach sooner rather than later.
Despite the overamplification of the QC threat, it is important to mention that only a portion of BTC’s supply is vulnerable to such an attack, roughly 1/3rd to be exact. These are the BTC held by publicly viewable addresses. The Bitcoin development team is reportedly looking at various upgradation options available to “Quantum Proof” the network. A Bitcoin Improvement Proposal (BIP) addressing quantum threats, BIP 360, has been proposed and introduces a new output type called Pay-to-Merkle-Root (P2MR).
On the other hand, Bitcoin maximalists like Michael Saylor have stated that the network is likely to remain impervious to quantum threats for the next decade. Critics of QC believe that the current threat is grossly overhyped and not in line with actual developments on the ground.
