In theory, a 4,000 qubit quantum computer could crack Bitcoin’s encrypted network in seconds. The 2022 IBM Osprey processor has a capacity of 433 qubits. Some believe a quantum computer capable of breaking Bitcoin's encryption may be a few years away. What's more, it is directly predicted that BTC will return to zero.

Quantum computers have the potential to crack Bitcoin

If you have a powerful enough computer, in theory, you can crack the two Bitcoin encryption algorithms, Elliptic Curve Digital Signature Algorithm (ECDSA) and sha256, and then control the Bitcoin blockchain. You can deposit free Bitcoins into your account, double spend Bitcoins, and you will have the ability to calculate the password of any Bitcoin address from that address.

Although the most powerful conventional computer currently takes N+1 years to crack Bitcoin. But in theory, there is a machine whose computing speed is not at the same level as the current machines. It can complete operations in a few seconds that would take tens of thousands of years for an ordinary computer. These ultra-fast devices are called quantum computers.

They are real and are currently being developed by the best minds in the world. Quantum computers, developed in secret by governments, could disrupt blockchains in just a few years. However, some quantum computer developers say that this anxiety is far-fetched and far-fetched; when quantum computing becomes powerful enough to attack Bitcoin, blockchain developers will already have the ability to fix this vulnerability. .

What is a quantum computer?

Quantum physics involves the study of structures at the atomic level and even smaller than atoms. When studying subatomic structures, the laws of classical physics break down and crazy things start to happen. Quantum computers take advantage of these properties to perform calculations faster than the most powerful supercomputers.

Traditional computers, including the cell phone you’re reading this on, operate on 1s and 0s. If something is "true" the transistor will register a 1, if it is "false" the transistor will read a 0. There are billions of transistors in every computer; since the first transistor was invented in 1947, transistors have become by far the most manufactured device.

But the basic units in a quantum computer can register 1s and 0s simultaneously, meaning quantum transistors are exponentially more powerful than ordinary computers.

IBM Osprey处理器

How could a quantum computer crack Bitcoin’s code?

Bitcoin uses something called the Elliptic Curve Digital Signature Algorithm (ECDSA) to sign digital signatures, and a cryptographic standard called SHA-256 to hash blocks on the chain.

For Bitcoin, a randomly selected private key is run through these algorithms to generate a public key. The Bitcoin protocol then uses this public key to create a Bitcoin public address.

A quantum computer can reverse this process and extract private keys from public addresses. Once this happens, Bitcoin's claim to be inviolable and unhackable is broken, and you can access any Bitcoin wallet you want and withdraw your coins.

It’s estimated that you’d need a quantum computer with at least 4,000 qubits—a unit of quantum computer power—to crack Bitcoin’s code. Today’s most powerful quantum computers are still far away.

So, how long until quantum computing threatens to become a problem for Bitcoin? Depends on who you ask.

On the quantum side: Google CEO Sundar Pichai says "in five to 10 years, quantum computing will break encryption as we know it today." London-based cryptography firm Post - Andersen Cheng, CEO of Quantum, said, "Pichai's five-to-10-year forecast is based on commercializing quantum computers; no government will let anyone know they have a 'stadium-sized' machine hidden in an underground bunker," he said. of a giant quantum computer. For Pichai to sell Google's quantum computer to other companies, it must be stable and practical. But for a government computer, none of that matters. "Maybe two years, as long as you can Start cracking the encryption."

On the crypto side: Vitalik Buterin, co-founder of Ethereum, is also unimpressed. He said, "For every encryption algorithm that a quantum computer can break, we know that we have a substitute that a quantum computer can't break." Blockchain developer Peter Todd also said, "This makes no sense because Google's quantum computer The breakthrough is for a primitive type of quantum computing, and we don't even know yet if it's possible to scale a quantum computer."

What should we do now?

Now, it’s up to the blockchain and cryptography communities to build a quantum-safe blockchain. An important milestone is the competition to create a post-quantum encryption algorithm hosted by the National Institute of Standards and Technology (NIST), a standard-setter in the cryptography community. Algorithms driving quantum computer-resistant blockchains. Funding from institutions such as the National Research Council of Canada and the British government has also been pouring into initiatives that ultimately aim to help develop quantum-safe blockchain technology.

If you’re considering adding a cryptocurrency or blockchain component to your business and these quantum supremacy news have made you skeptical, that skepticism is unfounded, at least in the short term. Blockchain, Internet mathematics, computers and cryptography have brought us current privacy protection at the individual and even national levels. If all passwords and firewalls can be cracked, the security of nuclear weapons is a far more worrying issue than cryptocurrency. . Bitcoin holders seem to be living in a state of quantum uncertainty, but for now, all other aspects of our society are here to stay.