Friday, 23 October 2026

Faster than n log n? David Harvey weighs an AI-era multiplication claim

David Harvey (UNSW Sydney), co-author of the 2019 O(n log n) integer multiplication algorithm, has posted a note on a new manuscript from an unnamed “American technology company” claiming O(n(log n)^1−ε) with ε = 2⁻¹⁸². That makes the exponent of log n about 0.99999… with 55 nines.

He chooses his words carefully: the result is “possibly correct”, he hasn’t checked the proof in detail, and he would like a Lean formalisation, which doesn’t exist yet. He used Claude to help him read the paper.

Harvey, “On the recently proposed o(n log n) integer multiplication algorithm” (PDF, 20 Oct)

A four became a five: what goes wrong when an AI translates its proof into Lean

NPR’s Geoff Brumfiel looks at checking AI-made mathematics. Cambridge’s Anders Hansen found that in OpenAI’s Millennium Prize proof, the Lean version has one constant changed from 4 to 5. The formal proof is therefore weaker than the written one, even though it compiles. Daniel Litt and colleagues found a subtle error that sank an entire AI-written algebraic geometry paper.

Anthropic and OpenAI are each putting about $5M into an initiative that will partly fund checking of AI-assisted results. On Tao’s blog, Tristan Buckmaster argues that the field has to protect the credit owed to its students and postdocs.

NPR (via WWNO) · Buckmaster guest post, Tao blog (21 Oct)

Jailbreaking the Switch 2 through a BASIC interpreter

Sammy Hajhamid (pepsipu) describes ns2jb, which he says is the first software-only (tethered) Switch 2 exploit, on firmware 23.0.1. The entry point is SmileBASIC 4: in REMOVE, position + count wraps around a 32-bit int. That leads to a heap overflow in the fs sysmodule’s path normalisation, then a faked PID 1, then native code.

Codex agents did much of the hunting, driven through a harness of JetKVMs and a Bluetooth light switch that pressed the power button after each crash. The agents’ WebKit attempt failed.

pepsipu.com

Your MCU probably escaped the eMudhra CA mess

This follows yesterday’s tiny-integer CA keys. Daniel Mangum points out that bare-metal and RTOS firmware usually ships a small, hand-picked trust store, so it never trusted the eMudhra root. Zephyr’s HTTP GET sample, for example, bundles only GlobalSign R1. Linux-based boards that pull in a full distro CA bundle are not so lucky.

danielmangum.com

WorldTUI: a 360M-parameter model that only pretends to be a terminal

Simon Edwardsson trained a cut-down Qwen2.5-Coder with a 333-token vocabulary to predict which screen rows change after each raw keypress. No shell runs behind it. Training used about 336k synthetic Docker episodes (with 1.2% simulated typos) and 75 GPU-hours on a 4090. A DAgger-style self-correction pass took one benchmark from 24/47 to 38/47. It runs in the browser as a 208 MB int4 download.

simedw.com

“The compiler was supposed to end programming too”

This essay starts with IBM’s 1954 promise that FORTRAN would “virtually eliminate coding and debugging”, then works through The Last One (1981) and Brooks’s split between accidental and essential complexity. It cites METR’s finding that developers felt 20% faster while measuring 19% slower. Its forecast is that specs and tests become the main artifacts, and that verification becomes a career of its own.

hrih.si

Reproducing an outage on purpose: Postgres recovery_prefetch

Jeremy Schneider built a small, repeatable rig to show how prefetch on a replica turns sequential reads into 8 KB random reads, up to 16× the IOPS. The rig is 2-CPU boxes, 500-IOPS disks and pgbench at scale 640. Add synchronous replication and writes on the primary stall: TPS sat at zero for more than 30 minutes. He argues the setting should default to off.

ardentperf.com

Triangulating 3.7 million map polygons in 489 ms

The GLMap team swapped constrained Delaunay for a new ear-clipping triangulator, earstrip (ISC licence). They measured each step separately: dent-only tests, a convex shortcut, strip output, spatial buckets and branch-free hit counting. Together these took one M4 Pro core from 2,931 ms to 489 ms, 14% faster than earcut.hpp.

globus.software

GitHub rebuilds Git storage for agent-scale traffic

GitHub’s Spokes system handles more than 100 billion operations a day. Its write quorums used to lock the whole repository and now lock per reference, which gave 3–4× write throughput in testing. New “virtual write replicas” make a write durable in Blob Storage before acknowledging it. GitHub names agents outright as the reason, and the remaining limit is a roughly 25 ms cross-region round trip.

GitHub Blog

US Championships: Rachael Li wins on debut; So stumbles into a playoff with Caruana

Rachael Li drew her last game with Black against Zatonskih to win the US Women’s title on 8½/11 at her first attempt. Alice Lee finished second on 8. In the open, last-placed Sam Sevian beat Wesley So after a 48th-move blunder. That ended So’s run of 48 US Championship games unbeaten, and Caruana beat Liang to draw level.

Their rapid playoff (two 15+10 games, then more rapid, then blitz, with no Armageddon) began at noon St Louis time on 22 October. The result wasn’t out when this page was written.

Chess.com · US Chess

Austin: both Mercedes get the upgrade, and the title could go this weekend

After Russell went back to the old spec in Singapore to give a comparison, Wolff confirmed that both cars will run the latest package at COTA. Antonelli (340) clinches if he wins while Russell (238) finishes 9th or lower and Hamilton (229) finishes outside the top four. Otherwise the fight moves to Mexico on 1 November. Rain is a risk this weekend, and Verstappen, who has won the last two races, says the bumps make him feel “like Robocop”. There is no new Piastri news.

Sky Sports · GPblog · PlanetF1

Music+Sound Awards: Saros wins both game music categories

Sam Slater and Daniel Avery won Gameplay and Cinematics for Housemarque’s Saros, worth a listen. Other winners:

• Feature film: Stuart Hancock, Stargazers
• Series: Chris Roe, The Lady
• Title sequence: David Arnold and Lana Del Rey, 007 First Light
• Rising Star: Charlie Smith

New this week: Giacchino’s Klara and the Sun album (out 23 Oct) and Anna Meredith’s Wicker (30 Oct).

Televisual · Film Music Reporter

Gavin Higgins’ Clarinet Concerto premieres with Mark Simpson

The new concerto runs about 35 minutes in four “Nocturnes”, each drawn from a literary source and from queer nightlife. Mark Simpson premiered it on 17 October with the Royal Liverpool Philharmonic under Adam Hickox. The RLPS and the Royal Philharmonic Society co-commissioned it, and Bachtrack has a review.

Bachtrack

Venus slips between Earth and the Sun on Saturday afternoon

Inferior conjunction is at 04:00 UT on 24 October, 3 pm in Sydney. Venus will be about 40 million km away and 6° south of the Sun, a 0.75%-lit crescent, so there is no transit (the next is in 2117). This one favours far-southern observers. SOHO’s LASCO C3 camera is watching Venus cross its field until the 28th, and it then climbs into the dawn sky to meet Jupiter in November.

Universe Today

The first train delayed by space weather, re-dated by a typo

A solar storm disrupted telegraph signalling and held up the 10:05 pm from Exeter by 16 minutes. An 1871 Nature note put this in 1841, but the line didn’t open until 1846. Jim Wild’s team at Lancaster cross-checked timetables, aurora sightings and magnetometer records and pinned it to 18 October 1848.

ScienceDaily

Weekend: City Circle closed, 7 Bridges Walk on Sunday

On Saturday and Sunday there are no trains between Central and Wynyard via the City Circle. T2 Inner West has buses between Strathfield and Central (express trains still run), and the North Shore line runs Hornsby–Wynyard only. From Pyrmont, use the L1 or the Metro. Late on Saturday night, buses replace trains between Olympic Park and Central.

Sunday’s 7 Bridges Walk has its village at Pyrmont Bay Park, so expect crowds on the doorstep. On Saturday, Hilary Duff plays Afterpay Arena and the Wanderers have a double-header at CommBank Stadium.

Transport NSW: City Circle / T2 · Olympic Park late night · 7 Bridges Walk · Events