Shor's algorithm is possible with as few as 10,000 reconfigurable atomic qubits

An academic preprint estimating that Shor's algorithm against elliptic-curve cryptography might be run on far fewer qubits than long assumed, using reconfigurable neutral-atom hardware. The authors suggest the discrete-logarithm problem on a 256-bit curve could be solved in days on a system with on the order of tens of thousands of physical qubits.

Like the parallel Google estimate, this is a resource estimate for hardware that does not yet exist, dependent on assumptions about error rates and architecture, and the authors note substantial engineering challenges remain. It is one input to the timeline question, not a demonstrated attack, and the gap between estimate and working machine is exactly what is contested.