Quantum computing: An existential risk of Bitcoin?
A few months ago, the technology giant Google announced a breakthrough through the introduction of the “Willow” chip. The computing power of the quantum computer is exponentially stronger than that of a conventional supercomputer, which raises questions about the safety of Bitcoin and Blockchain.
Quantum computers (English = quantum computer) carry out complex calculations by the principles Use quantum mechanics. This enables you to solve certain tasks such as optimization, cryptography and simulations much faster than classic computers. According to Google, your Willow chip is able to solve complex problems in less than five minutes, for which a supercomputer would have needed about 10 quadrillions years. However, the danger to Bitcoin is less than a skeptic.
Bitcoin wallets still safely before Quantum Computing
Bitcoin uses the cryptographic hash function SHA-256 to secure transactions and generate new blocks by solving complex mathematical puzzles. Many other systems, such as SSL certificates and secure data storage, also rely on this function when encryption. Quantum computers could endanger the security of SHA-256 by breaking the underlying cryptographic algorithms. This would allow a quantum computer to crack the private key of an address. Satoshi Nakamotos Wallet with over a million bitcoin (at today's price of USD 105 billion) would be a popular destination.
On the one hand, today's quantum computers are not nearly strong enough for cracking Bitcoin encryption. The computing power of the technology is measured in so -called quantum bits (“qubits”). It is estimated that there would be a risk to Bitcoin Wallets over 13 million qubits. For comparison: Google's Willow chip reaches less than 105 quBits. Bitcoin can also protect itself by switching the blockchain to quantum -resistant cryptographic algorithms. These already have researchers developed.
Danger for Bitcoin mining
For mining a quantum computer would be a danger if it Proof-of-Work-Inatzally, puzzle solves faster than classic miners. That could go to one 51%attack lead in which a single entity controls the majority of the mining performance. In this scenario, the quantum computer would be able to change the rules of the network and enrich yourself.
Although strong quantum computers could theoretically solve the puzzles much faster than conventional computers, this threat is alleviated by several factors. First, the quantum computer performance is expected to improve over several years due to the technical challenges in scaling the qubit numbers and implementing a robust error correction over several years.
If the first quantum computers come onto the market, the effect of a new computer is weakened. The calculation intensity and competition of the mining increases through every participating quantum computer. In addition, quantum computers run only a few seconds today. In order to extend this term, advanced error correction techniques with millions of more qubits are required. This limits the immediate threat to Bitcoin until quantum -resistant mechanisms are used.
Malicious actors have different goals
Attacker in possession of a quantum computer will target SHA-256 blockchains such as Bitcoin systems with more direct value, such as the far less complex crack in RSA encryption. This is used for safe communication, banking and government data. Anyone who is stored by his assets at a bank instead of Bitcoin is also at risk from quantum computers.
Malicious actors could also take advantage of weaknesses in critical infrastructures or steal sensitive corporate information. Due to their broader economic and strategic effects, these goals have a much higher priority than Bitcoin. Nevertheless, the awareness of the blockchain community remains important. A change to quantum -resistant algorithms is theoretically easy to implement, but requires a clear consensus. If this is reached too late, short -term complications could occur.
