Physics Practical Magic

Cracking modern internet encryption may require 100 times fewer quantum qubits than previously thought.

March 31, 2026

Original Paper

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

Madelyn Cain, Qian Xu, Robbie King, Lewis R. B. Picard, Harry Levine, Manuel Endres, John Preskill, Hsin-Yuan Huang, Dolev Bluvstein

arXiv · 2603.28627

The Takeaway

It was long believed that breaking the codes protecting the world's data would require millions of qubits, far beyond today's technology. This new analysis shows that by being smarter with the math, a quantum computer with just 10,000 qubits could do the job, bringing the 'quantum threat' much closer to reality.

From the abstract

Quantum computers have the potential to perform computational tasks beyond the reach of classical machines. A prominent example is Shor's algorithm for integer factorization and discrete logarithms, which is of both fundamental importance and practical relevance to cryptography. However, due to the high overhead of quantum error correction, optimized resource estimates for cryptographically relevant instances of Shor's algorithm require millions of physical qubits. Here, by leveraging advances i