How to compute a 256 bit elliptic curve key with 50M Toffoli gates

&quot;At 10% threshold, assuming a 10-μs code cycle and non-local connections, one key can be generated every 10 minutes using 6000 modules with 1152 physical qubits each.&quot;<p>1152 qubits sounds like the D-Wave chips. So does that mean 6000 D-wave chips ?<p>Even if you reverse the calculation, that would be 60000 minutes on 1 chip, which is about 42 days only, so. Quantum Too Good

About 5 years ago I wrote my master thesis on quantum computing, specifically on the construction of quantum circuits. As these circuits are generally unitary matrices an interesting question is: Given a set of gates that operate on one qbit or two qubits (controlled gates) and a target unitary matrix (e.g. fourier transform or the hamiltonian of a physical system of interest such as an Ising model), can we find an optimal&#x2F;minimal arrangement of those gates to approximate or exactly match the target matrix.<p>Back then I modelled the quantum circuit as a set of unitaries (by parametrizing them through their generator), that operate on one or two qubits, set a limit to the amount of steps and the amount of controlled gates and then threw different optimization algorithms at it. I got the best performance using simple dense neural networks. What&#x27;s cool is that I could generate a training set really quickly since I could just randomly build tensor products of unitary matricies to create billions of unitaries of up to 7 qubits in minimal time and then just see how close I can get given a fixed length for the quantum circuit and a fixed number of control gates.<p>I really liked this approach and it was fun to work on. However it was ultimately limited as the size of the matrices scales exponentially with the number of qubits.

Related:<p><a href="https:&#x2F;&#x2F;arxiv.org&#x2F;abs&#x2F;1905.09749" rel="nofollow noreferrer">https:&#x2F;&#x2F;arxiv.org&#x2F;abs&#x2F;1905.09749</a> | How to factor 2048 bit RSA integers in 8 hours using 20 million noisy qubits

I have a feeling the quantum-crypto conversation is going to take off like a rocket after IBM does their Quantum System 2 presentation later this year.

Doesn’t this mean crypto has a major problem ?

RIP Passkeys.