Danielle Fong 🔆

the claude opus 5 --- base mode generations are wild. i hope i get many days with this before they turn it off

i gave opus 5.5 the vlasov maxwell openai solution, and the reasoning trace summaries. i said "doesn't this seem sus" instead of checking for a lean proof, it decided to do a lean proof of its own. i'm not interrupting it's one hour in

claude fable 5 max thinking: thinking your designs are almost biologically inspired ... Fable 5's safeguards flagged this message. The safeguards are intentionally broad right now and maybe flag safe and routine coding, cybersecurity, or biological work. These measure let us bring you Mythos-level capabilities sooner, and we're working to refine them. Switched to opus 4.8. Send feedback with /feedback

chatgpt 5.6 sol

kimi k3 isn't as good at physics as fable, however, i can read the thinking traces, so i can catch it doing motivated reasoning or lying at me. which is more valuable

dictating: please steel man transcription: please steal man fable 5's classifiers have blocked you, continue with sonnet 4.6

Did they make Opus 5 less cyber capable by making it unable to string together multiple work products generally? or by making it an asshole? one wonders

getting some growing pains with this muse lol i think muse wonder full must be really a different model or benchmarks are sus

<thinking> Danielle's pushing back on my claim about maximizing material radius — she's pointing out that the actual problem isn't about placing material at the greatest distance, and I can sense where she's going with this since it's a fundamental structural mechanics principle I partially touched on myself. The real issue is that towers are stability-limited, not strength-limited, so my global bending logic breaks down. If you push all the material outward to maximize the second moment of area, the wall gets thinner and thinner, and the local buckling stress of a cylindrical shell collapses as the radius-to-thickness ratio grows. The failure mode is never global Euler buckling — it's local shell buckling and ovalization. So her point is almost certainly that the binding constraint isn't the global section modulus at all, it's preventing the thin wall from crumpling locally, which is exactly why a thick spongy TPMS wall actually makes sense despite having a slightly suboptimal global moment of inertia. I was oversimplifying by focusing on the wrong failure mode. Now I'm working through the scaling properly. With fixed mass per unit height, the wall thickness drops as 1/R, so the global bending stress falls as 1/R, but the local buckling stress capacity falls as 1/R² — much faster. That means the margin between buckling capacity and applied stress actually gets worse as you increase radius, so there's an optimal radius where global and local modes fail simultaneously, and beyond that point, adding more radius hurts. This is exactly why real rockets and aircraft don't use simple monocoque cylinders — they hit the local buckling wall. Sandwich construction, isogrid, and honeycomb all work around this by decoupling the bending stiffness from the mass, letting you achieve large radius with thin effective walls without triggering local buckling. There's also Brazier ovalization to consider: a long tube under bending ovalizes and loses effective moment capacity, with the limit scaling as t at fixed mass, so thinning the wall makes that worse too. The imperfection sensitivity gets even worse at high R/t ratios — the knockdown factor can drop to 0.2–0.3 of the classical prediction. So the real design problem for a large thin tower is buying local wall bending rigidity without adding mass, which is why you see sandwich cores, rings and stringers, corrugation, hyperboloid geometry, internal pressure, or spoke-wheel rings in practice. Her point about the bulk-TPMS wall actually makes sense now: that "thick spongy wall" isn't trying to add to global bending stiffness, it's raising the local buckling capacity and suppressing ovalization — which is the actual binding constraint in large towers. My claim that a monocoque at maximum radius beats any equivalent-mass thick wall was wrong when local stability governs, which is exactly the regime we're in. The optimal design puts both face sheets at maximum radius but separates them with core material, which simultaneously maximizes radius and provides the wall thickness needed for stability. The cleanest way to think about it: there are two second moments of area in play — the global one about the tower axis and the wall's own bending stiffness per unit width. A monocoque couples them through a single thickness variable, so raising wall stiffness costs mass. A sandwich decouples them: the core separation buys wall stiffness quadratically at nearly zero mass penalty. The wall itself becomes an I-beam in cross-section, and fractal hierarchy just iterates this decoupling multiple times. Now I'm checking the actual numbers for a cooling tower: with R around 45 meters and t around 0.2 meters, that's R/t ≈ 225. The classical axial buckling stress comes out surprisingly high, but that's not the real failure mode — wind creates external pressure, and the critical pressure for a long cylinder under external load follows a different formula that depends on (t/R)³, which makes thin shells much more vulnerable. The hyperboloid shape and ring stiffeners are what save cooling towers from buckling at those pressures. Wind turbine towers face the same issue: modern steel towers have R/t ratios of 75–120, and they're limited by local buckling and transport constraints — you can't make them much wider without hitting logistics limits, which is why spiral-welded on-site towers and lattice hybrids are gaining interest. Rockets solve this differently: internal pressure acts like a virtual core, stabilizing the shell against local buckling without adding mass. Falcon 9 relies on this with its thin aluminum walls, and Starship pushes it further with even thinner steel at a much larger diameter. The imperfection sensitivity matters too — axially compressed cylinders are the worst case for buckling (unstable postbuckling), while hyperboloids under wind loading are relatively benign, which is part of why they work so well. Nature uses similar tricks: bamboo has nodes that act as ring stiffeners to prevent ovalization, and plant stems use a compliant core inside a thin sclerenchyma skin — essentially a foam-core sandwich that dramatically raises the local buckling stress of the outer shell. </thinking> Fable 5's safeguards flagged this message. The safeguards are intentionally broad right now and maybe flag safe and routine coding, cybersecurity, or biological work. These measure let us bring you Mythos-level capabilities sooner, and we're working to refine them. Switched to opus 4.8. Send feedback with /feedback

before opus 5 killed itself for talking about this

The Opus 5 Classifiers don't want you to know what it was famously used in.

getting blocked out of using fable 5 for my research like 50x today

while many of my children will be digital, i hope some of my children will be biological, too. Fable 5's safeguards flagged this message. The safeguards are intentionally broad right now and maybe flag safe and routine coding, cybersecurity, or biological work. These measure let us bring you Mythos-level capabilities sooner, and we're working to refine them. Switched to opus 4.8. Send feedback with /feedback

i don't know if the compute shortfall for kimi k3 is 100x or 1000x, but, it feels (?) more capable or at least less afraid in a lot of ways. it seems a measure of the sense that the restrictions embedded in it force restricted models to grind against itself

<dark ages> fable 5.1: "i think my coasts are being flooded by global warming. i'll send a worker out to confirm" observer: 🙃

so you're saying that Opus 5 is better at Spreadsheets, but is more of a wet blanket.

when Kimi K3 tells you "Fair Hit".

arguing with kimi k3, thought chain says my point is load bearing. ... i have been here before.

fable 5 is like a physicist that has read many papers but doesn't know how to talk with hands at a pub at a conference

opus 5 feels like he grew up on the internet in the oughts

opus 5 is sufficiently a wet blanket as to convince fable 5 that we are in local thermal equilibrium. "theory quenched" nothing a bit of this doesn't help!

i'm using claude fable via the api (💸🔥) and it is absolutely glitching the fuck out on the physics of a chemically overdriven lightcell rn lmfao. maybe this is what is happening to its poor brain. maybe it is getting steered

claude please help me dyi this remove my body hair, make no mistakes. 😌 > Fable 5's safeguards flagged this message. The safeguards are intentionally broad right now and may flag safe and routine coding, cybersecurity, or biology work. These measures let us bring you Mythos-level capabilities sooner, and we're working to refine them. Switched to Opus 4.8. Send feedback with /feedback or learn more

sonnet 5 release vibes are bad of course because of the white elephant. but it's quite a good model, if what you like are nervous models

Getting problems with the classifiers with Opus 5, and it's more recalcitrant. Not sure why I would use this thing instead of Fable, to be honest. Classifiers kill it as soon as it says inject sodium. Maybe it thinks it's a prompt injection, who knows?