SITUATION EXPLAINED: Anthropic researchers used Claude Mythos Preview to find genuine new mathematical weaknesses in cryptographic proofs • HAWK, a post-quantum digital signature scheme under NIST review, survived two years and two rounds of expert human review • Mythos cut HAWK's effective key strength in half in just 60 hours of semi-autonomous work • Separately, Mythos improved the best-known attack on seven-round AES (not the full cipher) by 200-800x • It did this using a novel technique…