David Hoffman

This is what they saw.

The Google paper is talking about a reduction of 20X, an improvement in Shor's algorithm that could break Bitcoin and Ethereum's cryptography.

When I say a 20X improvement, I'm talking about the number of physical qubits required to actually break ECDSA, which is the signature scheme for Bitcoin and Ethereum.

Exactly.

That's right.

And previous estimates were it would take tens of millions of qubits to do this.

Well, they just released it in

Improvement to the algorithm, to Shor's algorithm, that now make it take only 500,000 physical qubits.

And so in a runtime of about nine minutes, if they had the appropriate hardware, again, those 500,000 physical qubits, it would only take nine minutes.

for them to go attack Bitcoin or Ethereum and yoink the keys.

And also, this is not just limited to grabbing quantum vulnerable assets from Bitcoin or Ethereum or other chains.

It also enables on-spend attacks.

So they can intercept transactions before they confirm.

within the block time of something like Bitcoin, within nine minutes, they could intercept a transaction.

Say I send Bitcoin for myself to you, a quantum computer with this amount of hardware could go and yoink and intercept that transaction.

So this breaks Bitcoin, basically.

It also breaks everything else.

It breaks Ethereum.

It breaks everything in crypto if we had that level of hardware.

That's exactly right.