The Nightly Build.
Tech News

Claude halved the security of a post-quantum signature scheme

The flaw it found in HAWK had survived two years of expert review, and Anthropic says nothing in production has to change.

3 min read2026-07-30
Cryptography

Claude cut the effective key strength of HAWK in half1

Anthropic's Claude Mythos found a hidden lattice symmetry in HAWK, a post-quantum signature scheme that had survived two years of cryptanalysis. It used the symmetry to halve the effective key strength: for HAWK-256 the cost of the best known attack falls from 264 to 238, from infeasible to trivial. The run took about 60 hours and roughly $100,000 in API calls. A second result, a meet-in-the-middle procedure the model named the Möbius Bridge, runs 200 to 800 times faster against a seven-round research version of AES, but it never touches the full ten-round cipher and would need more than 400 octillion messages to mount.2 Anthropic says no deployed system is affected and no production software has to change.

Robotics

MIT robots plan the next move before finishing the current one3

The technique, called VLASH, lets a vision-language-action model predict where the robot will be once its current action finishes and plan the next one while that action still runs, erasing the pause between chunks that makes learned policies stutter. On pick-and-place the arms run about twice as fast, and the reaction gap between chunks shrinks more than thirtyfold, with no added planning compute.4 The group, led by MIT's Song Han and presented at IROS, showed it on table tennis and Whack-a-Mole as well as sorting and stacking.

Astrophysics

Swift caught a black hole shredding a star far from its galaxy's core5

The flare sits more than 30,000 light-years from the galaxy's center, the farthest offset ever recorded for an optically discovered tidal disruption event, and marks a wandering black hole of about a million solar masses rather than the central engine such events usually trace. For a few months the disruption outshone its entire host galaxy in ultraviolet, briefly radiating like 10 billion Suns some 750 million light-years away in Cetus.6 It was first pulled from the noise in November 2025 by an AI classifier sifting the roughly half a million transients the Zwicky Transient Facility logs each night, which flagged its improbable location as a likely disruption.

Semiconductors

Two colors of laser light steer a current through a semiconductor7

University of Michigan physicists overlapped two infrared laser pulses of different colors inside a device and launched a directed beam of electrons with no applied electric field, aiming it by rotating the light's polarization. The direction comes from quantum interference between two absorption paths to the same final state, one adding to the motion and the other cancelling it, so the current sweeps like a lighthouse beam as the light changes.8 The work, in Physical Review Letters, points toward optical control for sensing, imaging, and telecommunications rather than any near-term device.

Chemistry

Twisted light tells a molecule's left hand from its right by the debris9

Physicists at the Tata Institute and two IITs shaped laser light to carry orbital angular momentum and found it breaks the left- and right-handed versions of a molecule apart at different rates, so the fragment counts alone reveal which mirror image is present. Distinguishing these enantiomers is a standing problem in drug chemistry, where the two hands of a molecule can behave very differently in the body and current methods are slow or insensitive.10 The result, in Science Advances, offers the twist of the light itself as a faster probe of molecular handedness.

Sources

  1. Anthropic · Discovering cryptographic weaknesses with Claude
  2. CyberScoop · Anthropic's Claude Mythos finds weaknesses in encryption algorithms
  3. MIT News · Making robots faster by helping them think ahead
  4. Interesting Engineering · MIT's new model cuts reaction delays by 30 times
  5. NASA Science · Swift Sees 'Wandering' Mega Black Hole Shredding Star
  6. Universe Today · A Wandering Black Hole Meets a Wandering Star
  7. University of Michigan · 'Electron lighthouse' illuminates new physics
  8. ScienceAlert · Physicists Created an 'Electron Lighthouse' That Steers Current With Light
  9. Science Advances · Twisted topological light illuminates molecular chirality
  10. Phys.org · Twisted laser light distinguishes mirror-image molecules by their fragment counts