Matthew Green warns AI could shake trust in public-key cryptography
What happened
On 9 October 2026, Simon Willison reported that cryptographer Matthew Green gave probability estimates for AI's impact on public-key cryptography: a 1% chance we live in a Minicrypt world where public-key cryptography is impossible, and a 15% chance we substantially lose trust in existing public-key algorithms. Green noted that AI's pace of producing unexpected discoveries and humanity's pace of changing standards differ by orders of magnitude, and that only advance preparation can recover from such shocks.
Written by AI from the reports · updated 7 d ago
Timeline
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- Simon WillisonQuoting Matthew Green
Cryptographer Matthew Green says there is a 1% chance we live in Minicrypt, a world where public-key encryption is impossible, and a 15% chance we functionally lose confidence in our existing public-key encryption algorithms. He notes that the speed of AI producing surprises and the speed of human beings replacing standards are orders of magnitude different, and that you only recover from such a surprise if you do the preparation in advance.
Heat of this event
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