How Quantum Computers Will Destroy Bitcoin and Blockchain

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How Quantum Computers Will Destroy Bitcoin and Blockchain

After receiving numerous messages in response to my statement, “Quantum Computers Will Destroy Bitcoin and Blockchain,” many people expressed confusion and skepticism. I had to triple-check my idea to make sure it wasn’t completely off base—and that I wasn’t, in fact, losing my mind.

Yes, it's true, and I stand by my statement. I'm here to provide some context for this position with supporting evidence and research. Quantum computing has the potential to dismantle the underlying technology and security that Bitcoin and many other cryptocurrencies rely on. The current encryption standard that Bitcoin uses is AES-256. For traditional computers, cracking AES-256 would take billions of years. For quantum computers, it could take minutes. Just last month, a team of researchers in China claimed to have made significant advancements toward breaking RSA encryption using quantum computing. However, there is still debate and skepticism about these claims—Forbes recently clarified that China has not yet broken military-grade encryption with quantum computers (Forbes).

Despite this, AES-256 remains at risk in the future as quantum technology advances. This could eventually lead to the ability to modify or alter the blockchain and, more importantly, enable attacks on wallets by fully describing their keys. In such a scenario, someone could easily take over another person’s wallet.

This isn’t a far-fetched idea; many people can see the writing on the wall when it comes to encryption vulnerabilities. Some are advocating for a quantum-resistant protocol where possible. Unfortunately, for the BTC blockchain, this may not be achievable. According to CSO Online, the National Institute of Standards and Technology (NIST) has already published a timeline for quantum-resistant cryptography standards. However, they emphasize that organizations will need to act quickly to protect critical systems. This led me down another rabbit hole, where I found sparse but valuable information from some experts. Some argue that Bitcoin can’t fork to a quantum-resistant model. Technically, it could, but old or inactive wallets would still remain vulnerable to quantum attacks.

This brings me to my next point: who is working on a quantum-resistant protocol or a quantum-safe blockchain? It turns out only one coin, as of now—QRL (Quantum Resistant Ledger)—is specifically focused on this, with Cardano (ADA) also working towards implementing quantum-resistant protocols (QRL Whitepaper, Chain.com on Quantum Threat). Additionally, one other project is developing a Layer 1 Web3 technology for quantum-resistant code. Cardano has even outlined its proactive approach to quantum computing to ensure future security (SourceDAO on Cardano).

I can’t be the first to have this idea and think, “Why aren’t more people talking about this or at least preparing for the quantum digital revolution that’s quickly approaching?” As it turns out, I’m not the first. Many have predicted that quantum computers would eventually undermine blockchain and Bitcoin, but it was previously considered a fringe concept, a far-off possibility. Today, governments are racing to secure everything they can under new standards for quantum-resistant protocols. They are urging companies to implement these standards quickly, but realistically, most won't make the shift in time. Some experts predict that nation-states could achieve quantum decryption at scale by 2028… That’s just around the corner.

On the other side of all this, when “Q-Day” arrives, we will likely see a new blockchain ready for the quantum world. I would also assume that all cryptocurrencies will either transition by then or face extinction. It’s becoming clear to me that BTC won’t last forever, and something else will inevitably take its place.

Other considerations I didn’t discuss here but have covered in my other blog include the fact that most of the internet relies on AES-256 encryption, so when Q-Day comes, it will bring a host of other problems. The collapse of blockchain security might actually be the least of our concerns.

By: Nick DiRaddo