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2027 memory capacity is reportedly sold out

2026-08-07 @ 07:58:24Points: 65Comments: 46

Framework discloses data breach via Metabase 0-day

2026-08-07 @ 05:17:57Points: 81Comments: 30

New Orleans is testing Carbyne’s AI-powered Emergency Call Triage software

2026-08-07 @ 00:37:30Points: 60Comments: 80

New Mexico court orders Meta to pay $567m over harms to children’s mental health

2026-08-07 @ 00:06:28Points: 287Comments: 188

Spin audit of SQD/QSCI quantum-chemistry benchmarks on iron–sulfur clusters

2026-08-06 @ 22:50:09Points: 13Comments: 1

Background, for anyone who hasn't followed this fight: IBM's iron–sulfur SQD results (Sci. Adv. 2025) are one of the flagship "quantum computers are useful for chemistry now" claims, and a published critique (arXiv:2501.07231) argues the quantum samples never beat classical selected-CI at matched cost. That argument is still live.

Both sides have been arguing about energies. Neither measured which electronic state these calculations actually converge to.

So I measured it. ⟨S²⟩ comes out between 4.7 and 7.0 depending on the system and the subspace size, where the target these papers name is a singlet at ⟨S²⟩ = 0. Every starting guess I tried lands in the same place, and the error at convergence is about the size of the spin-state ladder itself, which is the physics under dispute.

IBM ships a mitigation for this. Run exactly as shipped, using their driver, their recovery loop and their own spin_square() diagnostic, it moves the ground energy by under a nanohartree while making the subspace 4.00x bigger: 194,481 determinants against 48,600. It makes a singlet representable. It never produces one. Their solver also takes a spin_sq argument that would target the singlet directly, and the default pipeline never sets it.

I filed that narrow part on their tracker yesterday, before posting this: https://github.com/Qiskit/qiskit-addon-sqd/issues/337. A maintainer answered and closed it the same day, and his answer is the useful part. The flag, in his words, augments the sampled subspace by using alpha CI strings as beta strings and vice versa. That is a statement about which determinants span the space, not about what spin the returned state comes out in, which is exactly what the measurement says. He did not contest the numbers. The second question, whether the default path is meant to reach spin_sq at all, is still unanswered.

The obvious objection is that this is all my own reimplementation, so here's the part that isn't. IBM's data-availability archive for the flagship paper contains the raw hardware measurement records: 2,457,600 shots on [2Fe-2S] from December 2023, 3,163,742 outcomes on [4Fe-4S] from April 2024, plus the integrals and the optimized circuit's parameters. Running their shots through their own pipeline, [2Fe-2S] reaches low ⟨S²⟩ but sits 248 mHa off their own reference, and [4Fe-4S] converges to a spin-pure triplet, Var(S²) = 3e-6, a genuine S=1 eigenstate: a clean state, and the wrong one, 1,438 mHa from their reference.

Two things in that archive need no analysis from me at all. Their uniform-random null control matches or beats the hardware samples in every published [2Fe-2S] comparison. And their largest [4Fe-4S] runs, at subspace dimension 10⁸, trail their own classical HCI file by 149 mHa.

On the AI angle, since that's half of why this is on HN: Claude did the initial audit end to end in about 72 hours under my direction, and it's been through many rounds of adversarial review since. The part I'd defend as actually interesting isn't the speed. It caught five defects in its own work through pre-registered validation gates, one of them by cross-checking against IBM's own published energy tables, and it retracted its own strongest pro-quantum finding when the new instrument showed that result was a spin-sector artifact. AUDIT_TRAIL.md has the timeline. REPRO_MAP.md maps every claim to a file and a command that regenerates it.

If you want to kill this, and I mean that, here's how. Exhibit any state in a spin-completed ground manifold of these benchmarks with ⟨S²⟩ < 1. Or show me a quantum-sampled subspace at matched determinant count whose spin-identified energy beats HCI or CIPSI. Or get any shipped-pipeline run on IBM's archived samples to land ⟨S²⟩ < 1 and error under 50 mHa at once, with no spin penalty. The harness is in the archive and I'll publish whatever comes back, including if it's me who's wrong.

Preprint: https://doi.org/10.26434/chemrxiv.15006382/v1

The limitations section is real: comparison dimensions are fixed, the [4Fe-4S] reference is approximate, and the 58.6M "samples" file is deduplicated, so the shot-level distribution of their optimal-circuit numerics isn't publicly auditable. It's short. Worth reading before the hot take.

Welcoming the Nepalese Government to Have I Been Pwned

2026-08-06 @ 21:52:16Points: 158Comments: 25

Inside vLLM: Anatomy of a High-Throughput LLM Inference System (2025)

2026-08-06 @ 21:30:21Points: 109Comments: 5

Bioengineered chewing gum may offer a way to fight HPV and other microbes

2026-08-06 @ 21:18:32Points: 132Comments: 36

What is a product?

2026-08-06 @ 21:16:52Points: 60Comments: 36

AMD acquires Taalas to boost inference performance by etching models in silicon

2026-08-06 @ 20:23:11Points: 673Comments: 510

Quake – 30th Anniversary Update

2026-08-06 @ 20:21:19Points: 318Comments: 160

Herdr is joining Y Combinator. The runtime stays open

2026-08-06 @ 19:14:21Points: 212Comments: 147

My phone detects going on a run as “someone snatching my phone and running off”

2026-08-06 @ 18:26:08Points: 141Comments: 245

Improving GPT‑5.6 Sol in ChatGPT, expanding GPT‑5.6 Luna access for free users

2026-08-06 @ 17:02:04Points: 243Comments: 184

Taste Is All That's Left

2026-08-06 @ 17:01:33Points: 430Comments: 320

Launch HN: ProvenMetal (YC S26) delivers circuit boards in days instead of weeks

2026-08-06 @ 15:59:15Points: 206Comments: 145

https://provenmetal.com). You send us design files or specs and we give you assembled boards domestically in days.

The US produced 30% of PCBs globally in 2000, now they produce 4%. Chinese manufacturers have completely dominated this space at 55% of global production.

Now, the need for a domestic PCB supply chain is higher than ever before, yet the infrastructure has been dissolving over the last 2 decades. What is left is mostly small family run manufacturers (CMs) that have been operating in largely the same, labor intensive way since the early 2000’s.

When you place an order through a CM it typically takes several days to receive a quote and complete design for manufacture review, and then you have to source all of the components (the hardest part) and bare boards yourself, then wait anywhere from a few days to several weeks for the assembly and testing of those boards.

We started off assembling circuit boards out of a garage with prosumer grade equipment (NeoDen YY1, Glenbrook X-ray, solder paste stencils, and manual rework stations). We believed that by owning the manufacturing process, we could turn all the front of house automations inwards. But here’s the thing… manufacturing circuit boards with prosumer grade equipment out of a garage takes a huge amount of time. Suddenly we were spending 90% of our time assembling circuit boards instead of growing the business. We were completely capacity constrained, with fancy software automations that are not the binding constraint at low volumes.

Then we got our heads out of the weeds, took a step back, and realized that we were trying to solve the wrong bottlenecks.

These manufacturers are good at manufacturing and terrible at the front of house (quoting, DFM review, and part procurement). When you look at the full process, you realize that assembly is not the bottleneck. So we stopped trying to solve the problem that we can’t solve at this stage.

We measured the bottlenecks and nailed down the ones that we are best positioned to solve right now.

When a customer wants a domestically manufactured circuit board, it is not a straight forward process. We are making that process easy through front of house automation. A customer gives us their design files, and we automatically procure components, and co-ordinate bare board fabs and assembly houses to get quotes, design review, and manufacturing completed in a very tight loop.

How we solve part procurement (you can’t assemble boards with no parts!): When a user places an order with us, our system automatically sources their bill of materials across US and overseas distributors. However, when we work with customers during the design process, our plug-ins interact with KiCAD and Altium, sending the BOM to our ordering platform, which allows us to automatically procure components before layout is finalized.

KiCAD plugin: (https://github.com/proven-metal/provenmetal-kicad)

Altium plugin: (https://github.com/proven-metal/provenmetal-altium)

This enables us to order long lead time parts in advance, suggest alternatives if parts are out of stock, and solve the biggest bottleneck in the process. We store parts in our hq in SF, and then kit the boards and route them through our network. We also do long term storage of parts for long lead time items.

How we solve endless emails: Every manufacturer wants the same information in a different shape. There’s usually a few days of back and forth emailing to achieve clarity. We’re building a profile per manufacturer and sending the order to fit their requirements. This may sound trivial but it removes a multi-day round trip on most orders, which on a quick-turn build is a meaningful share of the time.

How to solve design review: Each manufacturer has individual capability sheets, and so we have a heuristic harness that Fable 5 uses to check the board for DFM issues. We’re building a streamlined process for end-to-end pcb manufacturing, but is that enough to solve the supply chain? Not a chance. Capacity is the problem, and no amount of smart software will solve it. We’re extracting real slack from the system today, that slack is finite, and at some volume the only remaining move is adding physical capacity. We think that’s where this goes.

We charge a simple margin on the order value depending on order complexity with fully transparent quote breakdowns. We took our first paying order in less than a week and we’ve done roughly $70k across 11 orders in 6 weeks.

We are very interested in your opinion. We’re working in a problem space that has problems everywhere, we’re constantly pulled in wild directions regarding which problems we solve and how we go about solving them. What do you know that we can learn from?

GitHub Actions and Pages are experiencing degraded availability

2026-08-06 @ 15:49:38Points: 408Comments: 334

Humans missed 1 in 3 threats approving AI agent commands across 40k game runs

2026-08-06 @ 11:58:07Points: 303Comments: 213

Mario Meets Pareto

2026-08-06 @ 11:24:53Points: 1048Comments: 160

Scientists discover Kelvin-Helmholtz Instability on the surface of the Sun

2026-08-05 @ 15:33:23Points: 232Comments: 46

Why Estonians invite strangers into their back gardens each summer

2026-08-04 @ 02:50:07Points: 80Comments: 37

Reverse Jevons Paradox

2026-08-03 @ 22:04:18Points: 31Comments: 21

Show HN: A free mini game that makes you a smarter fly fisherperson

2026-08-03 @ 18:04:56Points: 13Comments: 3

A quine in Piet – a GIF image that prints itself [video]

2026-08-03 @ 14:20:45Points: 8Comments: 1

I stopped trusting USB-C cable labels and started testing them

2026-08-03 @ 07:12:57Points: 190Comments: 157

São Paulo resident transforms degraded area into urban forest

2026-08-01 @ 21:02:26Points: 141Comments: 56

Atomic Clocks

2026-07-31 @ 21:58:03Points: 66Comments: 37

Learn how chips are made with this Rollercoaster Tycoon-inspired animation

2026-07-31 @ 07:37:13Points: 162Comments: 49

STV: A full-motion video codec for the Atari ST

2026-07-30 @ 17:46:32Points: 58Comments: 6

Parsers don't have to be complicated

2026-07-29 @ 11:15:50Points: 36Comments: 16

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