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sbierwagen

13,179 karma · joined May 23, 2010

Sam Bierwagen

http://sam.bierwagen.me/

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sbierwagen··on The quest to build a telescope on the moon
Sounds like the 1980 NASA/ASEE Summer Study at the University of Santa Clara, with the proceedings edited by the prolific Robert Freitas: https://ntrs.nasa.gov/api/citations/19830007077/downloads/19...
sbierwagen··on Infineon's CO2 Sensor Monitors Indoor Air Quality
I built a CO2 meter around a SCD30 five years ago: https://bbot.org/blog/archives/2024/05/19/pocket_co2_meter_b...

My takeaway is that it draws a lot more power than you'd expect, thanks to the incandescent light source, and unless there's quite a lot of airflow over the sensor, it'll exhibit self-heating at any poll rate under every ten minutes.

sbierwagen··on Infineon's CO2 Sensor Monitors Indoor Air Quality
Note that NDIR sensors use a surprising amount of power, since they're based around an incandescent bulb shining light through the sample volume. A CO2 wearable will need to be recharged once a day, like a smart watch.
sbierwagen··on Caught on camera: Satellite tracker photographs secret spacecraft
Amusingly enough, there's been some groundwork laid here by gravity wave interferometer constellations: https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Ant...

You could imagine a deep-infrared mission (longer wavelength, to soften the alignment requirements) launched into deep space (Jupiter+) where both the solar wind density is lower (reducing space weather perturbations) and reduced solar flux would reduce heat loads on the structure, (objects in Jupiter orbit get 3.6% as much light as in Earth orbits) making cooling easier. An interferometer design would also improve resolution. A not-widely advertised feature of the JWST is that, due to the same Rayleigh limits, its far infrared modes have dramatically lower resolution than its near infrared camera. A problem with a 6 meter mirror, less of a problem with a kilometer mirror.

sbierwagen··on Caught on camera: Satellite tracker photographs secret spacecraft
There's a hard physical limit (the Rayleigh criterion) on the resolution of an optical system by how big the open end is. You won't get "super zoom" capabilities without a satellite the size of a stadium. https://en.wikipedia.org/wiki/KH-11_KENNEN#Resolution_and_gr...
sbierwagen··on Nature’s Ghosts: The World We Lost and How to Bring it Back
How many apple trees are visible in this photo of an Idaho forest? https://www.planetware.com/wpimages/2020/08/idaho-best-natio...

Ceteris paribus, normal trees will always outcompete fruit trees because they don't have to waste any energy on fruit, and use that instead on trunk height, putting fruit trees in their shade and, eventually, starving them to death.

You can, of course, maintain an orchard of fruit trees, manually removing competitor species, but then we're talking about stationary farming, a technology that Plains Indians did not have ten thousand years ago.

sbierwagen··on Nature’s Ghosts: The World We Lost and How to Bring it Back
A forest turns solar energy into wood, locking up that energy in an inedible form. Grass, on the other hand, can be eaten by grazing animals and turned into meat. If you're living off the land but not farming, then you'd prefer it to be covered in grass instead of trees.

Grazing animals can prevent grassland from reforesting by eating the tree shoots, but they can't knock down mature trees. There is some evidence paleoindians would burn down forests to expand grasslands. https://en.wikipedia.org/wiki/Great_bison_belt

Thus, in some parts of the US, you can stand on a hill, look out at miles of apparently untouched land without a single permanent structure, but is as artificial and manmande as a golf course, crafted from thousands of years of invisible labor.

sbierwagen··on Nature’s Ghosts: The World We Lost and How to Bring it Back
>possibly carrying firearms regardless of any rules

Carrying long guns is legal on all BLM land. Discharging them may be restricted in some areas, though.

sbierwagen··on Can solar costs keep shrinking?
Heavy vehicles often run on 24V. (Trucks over 26k GVWR, earthmovers, military equipment)
sbierwagen··on A dishwasher can make or break a restaurant (2017)
Consider PV solar: https://ourworldindata.org/grapher/solar-pv-prices-vs-cumula...

In 2003, PV panels were a pretty darn mature technology. The technology was decades old. Modules cost about $5 a watt, one twenty fifth the price they were in 1975. More than two gigawatts of them had been installed worldwide. (Millions of panels!) No way could they fall in price by half, right?

Surprise. By 2010 another 38 gigawatts of solar had been installed, and the price per watt was down to $2.32. No way could they fall in price by half again, right?

Surprise. $1.02 per watt in 2012, and another 61 gigawatts installed. $0.52 a watt in 2017. $0.26 a watt today.

Just in 2022, the world installed 86 times as much solar as existed on the entire planet in 2003.

If you build a lot of something, it can get very cheap indeed.

sbierwagen··on There Is No Antimemetics Division (2018)
>To me, it made <cool scifi thing> about as fun to read about as... tedious government bureaucracy.

This is also the problem with Charles Stross' Nightmare Stacks. The concept was kinda funny in 2004, but by book number 10 it just gets tedious. The reader cries out, What is the point of all this, and Stross answers with a shrug.

sbierwagen··on Why the future of AI is neurosymbolic. (A rare optimistic post from Gary Marcus)
>Then ask it to convert the problem into each of those formal methods. Then use something like Mathematica on each formal method.

Draft, Sketch, and Prove from 2022 does something like this: https://arxiv.org/abs/2210.12283

sbierwagen··on The Sphere
There are tours available for the largest building in the world (by volume) https://www.boeingfutureofflight.com/tour

The height is nothing much, but the main factory is 2,607 ft (794 m) along the longest dimension.

sbierwagen··on The Great Lightbulb Conspiracy (2014)
? https://www.usa.lighting.philips.com/consumer/p/ultraefficie...
sbierwagen··on Reasoning in Large Language Models: A Geometric Perspective
The paper doesn't make this point at all, but one thing you could do here is an AlphaGeometry-style[1] synthetic benchmark, where you have a geometry engine crank out a hundred million word problems, and have an LLM try to solve them.

Geometry problems have the nice property that they're easy to generate and solve mechanically, but there's no particular reason why a vanilla Transformer LLM would be any good at them, and you can have absolutely huge scale. (Unlike, say, the HumanEval benchmark, which only has 164 problems, which resulted in lots of accusations that LLMs can simply memorize the answers)

1: https://deepmind.google/discover/blog/alphageometry-an-olymp...

sbierwagen··on The semiotics of barbed wire fence
>Trumpflation

The CARES Act passed the Senate unanimously. If Trump caused inflation due to profligate spending, he did so with plenty of help from Democrats. He couldn't have stopped it even if he wanted to, that's far past the veto proof majority.

sbierwagen··on Facebook will soon use your photos, posts and other info to train its AI
2018: https://ai.meta.com/blog/billion-scale-semi-supervised-learn...

>In the case of ImageNet, the current state of the art accuracy is obtained by Facebook AI’s weakly supervised ResNeXt-101-32x48 model. It delivers 85.4 percent top-1 accuracy, outperforming by a significant margin the recently published EfficientNet network. . The model is pretrained on one billion public Instagram images, which contain 1,500 ImageNet-related hashtags.

sbierwagen··on The Fall of the House of Etsy
This isn't new. The Regretsy blog extensively complained about dropshippers in 2010.

The problem is that operating a two sided marketplace connecting small makers to customers just really sucks as a business. Tons of churn, intractable problems with quality and fulfillment, having to pay for a lot of customer service agents who fundamentally can't solve any problems, since they don't actually work for the person who makes the stuff, and can only hit the "refund" button.

Etsy has every reason in the world to want to get away from small sellers and move to high volume manufacturers, (who have actual QA and customer service departments, which a guy hand carving chess pieces in his basement doesn't have) and nothing to stop them. So the obvious thing happens.

(Except then you're competing directly with Amazon in its area of greatest strength, which historically has been corporate suicide...)

sbierwagen··on Show HN: Open-source GeForce NOW alternative with Stadia's social features
Starlink gets that latency by orbiting close to the Earth. At 525km, a Starlink bird completes one orbit in 95 minutes. For a twelve hour demand response orbit they'd have to be around 20000km high, more than one Earth diameter away, giving a far worse speed of light delay than just talking to a server one continent away.
sbierwagen··on What are third places? How do I find one?
Starbucks had a moment in the media spotlight when a store called the cops on two black men accused of loitering: https://www.nytimes.com/2018/04/15/us/starbucks-philadelphia...

In response, they updated corporate policy so that you don't have to buy anything to occupy a chair: https://www.eater.com/2018/5/21/17375806/starbucks-no-purcha... https://stories.starbucks.com/press/2020/use-of-the-third-pl...

Predictably, every chair is now occupied by a sleeping homeless person.

So now their choice is to either remove all the chairs, or potentially be mean to someone, and receive a firestorm of criticism. You can see which one they chose.

See also how MTA has removed all the benches from its stations, for the same reason: https://hellgatenyc.com/train-stations-should-have-benches

sbierwagen··on IBM Granite: A Family of Open Foundation Models for Code Intelligence
3B, 8B, 20B and 34B parameter model weights available here: https://huggingface.co/collections/ibm-granite/granite-code-...
sbierwagen··on Apple introduces M4 chip
Interestingly enough, Llama3 suffers more performance loss than Llama2 did at identical quantizations. https://arxiv.org/abs/2404.14047

There's some speculation that a net trained for more epochs on more data learns to pack more information into the weights, and so does worse when weight data is degraded.

sbierwagen··on The Hidden-Pregnancy Experiment: Could I Hide My Pregnancy from My Phone?
>Surveillance encompasses both policing and caretaking, Hamacher notes. In practice, its polarized qualities—“beneficial and harmful, intimate and distanced”—intertwine. Baby monitors use technology developed for the military. Many contemporary models run on CCTV.

What does Jia think "CCTV" is, exactly?

sbierwagen··on The Mirror Fusion Test Facility (2023)
Pure fusion bombs are very destabilizing, yes. The current nuclear arms control regime depends on uranium enrichment/plutonium production being heavy industry, requiring large facilities with unusual equipment.

A research program for EPFCG pure fusion weapons could be quite small, only requiring a few hundred people and little equipment that couldn't be manufactured indigenously. Test explosions could be done at the kilogram scale, producing no radiation detectable from orbit or seismic effects, then easily scaled to kiloton yields.

sbierwagen··on [dead]
Strange to say that AI is "changing everything" and then not link to a single news story about AI changing anything.

On a blog with no other posts? And no author name? Submitted by a HN user created seven days ago?

sbierwagen··on I should have loved biology (2020)
>the trouble comes from the fact that cells are too small, too numerous, too complex to analyze the way a programmer would, say in a step-by-step debugger.

It's like analyzing a Swiss watch if the back was welded on. You could send it though a shredder and analyze the fragments and work backwards to determine the size of the gears. But it's impossible to shred just one watch-- you have to shred a hundred thousand at a time, which are inevitably a complex mix of different watch models each with different minute lengths and hour durations.

Something I have felt is undertaught in introductory biology is how unknown human cells still are! No textbooks wants to list off a thousand proteins with "function unknown" next to them, after all. But to surprisingly large extent it's an undiscovered country. Just in the last few years we're discovering entire new species of RNA! https://www.science.org/content/blog-post/enter-glycornas

sbierwagen··on A curious phenomenon called 'Etak'
Stretching the definition a little, satellite TV had been a thing for years by then. Neiman Marcus was selling satellite dishes in 1979.
sbierwagen··on Descent 3 Source Code
There was Shattered Horizon from 2009, a zero g multiplayer shooter: https://www.youtube.com/watch?v=xWsHxTFPxSE

One fun feature was you could shut off your suit power to go into a stealth mode. This turned off all the HUD elements, and, amusingly enough, turned off most gameplay noises (the explosions and bullets whizzing by) because, in-universe, all those noises are generated by the suit computer, because space is silent!

sbierwagen··on Drones are crowding Ukraine's skies, largely paralyzing battlefield
>is the next obvious step drone carriers for extended range?

Yep. https://en.defence-ua.com/weapon_and_tech/drone_carrier_quad...

The drone carrier also acts as a radio relay, the other big thing limiting FPV range, since they both have to use low gain omnidirectional antenna and also operate very low to the ground, which is terrible for reception range.

sbierwagen··on AI is not your friend
He would probably argue that future LLMs are less likely to have their weights released. It is remarkable and strange that we have so many open-weights models right now, considering how much they cost to make.
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