Technology giant Google has made a noteworthy statement regarding the risks that quantum computers pose to current cryptography systems.
The company announced that authentication systems should transition to post-quantum cryptography (PQC) by 2029. This statement has reignited a significant debate, particularly regarding the future of blockchain networks like Bitcoin and Ethereum.
In December 2024, after Google introduced its “Willow” quantum chip, the general consensus in the cryptocurrency sector was that the threat was still far off. At the time, it was thought that the system, which only had 105 physical qubits, would need millions of qubits to break existing encryption methods.
However, the picture has changed somewhat in the last 16 months. Google is now providing a more concrete timeline, citing advances in quantum hardware, error correction technologies, and computational capacity. The company’s security engineering team stated that quantum computers pose a serious threat, particularly to digital signatures and encryption systems.
These risks are not just theoretical. Android 17 is beginning to integrate post-quantum signature protection, the Chrome browser supports post-quantum key exchange, and Google Cloud offers PQC solutions to enterprise customers.
The Bitcoin network uses the SHA-256 algorithm for mining and the ECDSA algorithm for signing transactions. ECDSA, in particular, stands out as a structure that can be broken by quantum computers.
A sufficiently powerful quantum computer could derive private keys from public keys using Shor’s algorithm. This could theoretically lead to the theft of Bitcoins whose public keys are visible on blockchains.
In the past, it was calculated that millions of physical qubits would be needed for this scenario to occur. However, Google’s advancements in error correction and its 2029 target suggest that this process could progress faster than expected.
On the other hand, some experts argue that quantum risk is exaggerated in the short term. According to CoinShares data, only about 10,200 $BTC are seriously at risk. A larger risk group of approximately 1.6 million $BTC is distributed across numerous wallets, making attacks practically more difficult.
*This is not investment advice.