River

1 million qubits can potentially crack a Bitcoin address.

Microsoft says its new chip creates a path to get there.

How long does Bitcoin have to become quantum-resistant? And what’s actually at risk?

We break it down in this 🧵 

Quantum computers (QCs) are notoriously difficult to operate.

Historically, QCs could only run for a few microseconds before breaking down, with massive operational costs to keep temperatures low and reduce noise.

That's not good enough to accomplish anything. 

Microsoft’s Majorana 1 release has cracked these hurdles, making it more reliable to run QCs at stable states.

This could bring us much closer to practical, large-scale quantum applications. 

Microsoft will need to reach a QC with a million qubits to tackle most industrial-scale problems.

The Majorana 1 chip is far from that scale now, but could reach the 1 million mark by 2027-2029, according to CEO Satya Nadella.

Is 1 million qubits enough to break bitcoin?

When ran for several days to weeks, a 1-million qubit QC could potentially crack bitcoin addresses via a long-range attack.

This thread explains how that would actually work
https://x.com/River/status/1885023891875082564

More realistically, we’d need a QC with 13-300 million qubits to carry out a long-range attack in 1-8 hours.

If achieved, this would put 5.9 million BTC at immediate risk.

Remember that the best QCs today have only 1,000 qubits.

Still, this breakthrough shortens the timeline to make Bitcoin quantum-resistant. Even if it's a decade away, addressing vulnerabilities early is crucial.

Our River Learn article walks through what’s at stake, and what the potential pathways ahead are:
https://river.com/learn/will-quantum-computing-break-bitcoin/