Hacker News Reader

sbierwagenon Charging electric vehicles 5x faster in subfreezing temps

When I bought a Model 3 last year I knew full well the issues with charging, temperature capacity loss, battery heating, etc. What I was surprised by was loss of regen! If the battery is below 20F or so then the firmware will only give it a trickle of regen braking. After all, it's effectively very fast charging, which a frozen battery can't handle.

I wonder if regen braking going to zero is behind some of the horror stories of sudden unexpected range loss in cold temps.

sbierwagenon Everyone knows all the apps on your phone

Push notifications. Apps have them on by default, websites have them off by default. 100% of Temu's valuation is because they pester users all the time with nudges to buy stuff, which works.

Normies don't turn off notifications. Over the last few years all my relatives have picked up smart watches, (thanks to cell carriers upselling them hard during phone replacements) and in any given conversation at family events they'll be glancing at their wrist every 100 seconds.

sbierwagenon Thinner Films Conduct Better Than Copper

Also posted on arxiv: https://arxiv.org/abs/2409.17337

sbierwagenon Designing Electronics That Work

Funny to see IPA called "toxic". In aircraft manufacturing it's considered the nice and friendly solvent in comparison to the stout stuff like MPK or MEK, and considerable effort is invested in convincing workers to use it when the big guns aren't needed. Or, natch, to get workers to wear gloves when working with solvents.

(Much discourse on industrial safety casts corporations as the bad guys, with considerable evidence, but it is still the case that much safety equipment is bulky or unpleasant to use. Ketone-proof gloves are thicker and less pliable than latex gloves, which is no small consideration when doing fine work under time pressure. Easier to just wear two layers and change the outer glove when it starts to break down. When do you know it's breaking down? When you feel it leaking through. When you feel that, doesn't it mean you're already getting skin contact with the solvent. Well, yes, but....)

sbierwagenon The Business of Phish (2013)

You're contradicting yourself here. You want tickets to be both cheaper and easier to buy.

They can't be both. The value of the ticket is just high. Either you pay in time, or money. Your enemy isn't ticketmaster, it's the 100,000 people who want to go to a 1,000 person venue.

sbierwagenon NASA to launch space observatory that will map 450M galaxies

>how does this polar orbit stay over the terminator?

Because it's launched at a angle greater than a straight north-south 90 degree orbit, so orbital precession will correctly follow the terminator. Depending on the orbital altitude this can be more than 140 degrees: https://en.wikipedia.org/wiki/Sun-synchronous_orbit

sbierwagenon "Big 3" science fiction magazines including Asimov's and Analog acquired

>although that was probably true of most scifi back then

In 1950? That was true of all media, including novels written by women. Is Dagny Taggart the protagonist of Atlas Shrugged?

sbierwagenon "Big 3" science fiction magazines including Asimov's and Analog acquired

One year later.

https://en.wikipedia.org/wiki/Analog_Science_Fiction_and_Fac...

>In the November 1948 issue, Campbell published a letter to the editor by a reader named Richard A. Hoen that contained a detailed ranking of the contents of an issue "one year in the future". Campbell went along with the joke and contracted stories from most of the authors mentioned in the letter that would follow the Hoen's imaginary story titles. One of the best-known stories from that issue is "Gulf", by Heinlein. Other stories and articles were written by some of the most famous authors of the time: Asimov, Sturgeon, del Rey, van Vogt, de Camp, and the astronomer R. S. Richardson.

sbierwagenon Geothermal power is a climate moon shot beneath our feet

Not in English.

sbierwagenon Sky-scanning complete for Gaia

One of today's lucky ten thousand. Most galaxies have a black hole at the center that mass at least a hundred thousand times more than our sun: https://en.wikipedia.org/wiki/Supermassive_black_hole

sbierwagenon Sky-scanning complete for Gaia

It takes 230 million years for the Sun to make one full orbit around the Milky Way.

sbierwagenon Sky-scanning complete for Gaia

It can't. The galaxy is assumed to be roughly symmetrical, and they fill in the missing data with what we can see on our side of the galaxy. It's "best" in the sense that it's the most accurate fiction, I suppose.

Gaia is good to about 13,000 light years: https://en.wikipedia.org/wiki/File:Galaxymap.com,_map_12000_...

The Milky Way is maybe 100,000 light years in diameter. So we're only getting good distance readings on a small fraction, and nothing behind the central bulge of our galaxy. The first won't improve until we send an astrometry telescope way outside the orbit of the Earth, for better baselines, and the second is going to need a telescope sent 10,000 light years out of the galactic ecliptic.

sbierwagenon De-smarting the Marshall Uxbridge

>It's an equivalent of self-compiling a software project after checking out its repo

I would not assign this to someone as their first electronics project. They would have to order all the components and get the PCB etched themselves. There's a fair bit of soldering, and a usable soldering iron is not cheap. And there's no undo button in hardware: if you solder something in backwards and pop it, you get pay for a new component and wait for it to ship to you.

sbierwagenon Tell HN: Impassable Cloudflare challenges are ruining my browsing experience

Polling for time sensitive things sucks. But for RSS, why not just poll once a day? Even if you're polling once an hour, a 304 response is, what, a few hundred bytes?

I just checked my own server logs, and HTTP 200 responses were 12.7% of the total requests against my rss.xml. Which is suboptimal I guess (I haven't made a single post this year) but isn't outrageously terrible.

sbierwagenon Plasticlist Report – Data on plastic chemicals in Bay Area foods

It's funny that you hold up ice cream as a paradigmatically unhealthy food, when most of the studies point in the opposite direction: https://www.theatlantic.com/magazine/archive/2023/05/ice-cre...

The state of nutrition science is so bad that I wouldn't believe most any study, though.

sbierwagenon Ham radio operators receive signals from Voyager 1 on Dwingeloo telescope

Not zero. Even a full Faraday cage only has 90dB or so of attenuation. But measuring it would be darn hard, since the attenuated signal would be swamped by diffraction, skyscatter and reflection by nearby objects of the stronger side lobes.

sbierwagenon Satellite powered estimation of global solar potential

>(the second is that Wh for energy is as silly as speed hours for distance)

This would be a devastating own if a single Joule wasn't exactly equal to a Watt-second.

sbierwagenon New LLM optimization technique slashes memory costs

Congrats, you have independently reinvented the Hardware Overhang hypothesis: that early AGI could be very inefficient, undergo several optimization passes, and go from needing a datacenter of compute to, say, a single video game console's worth: https://www.lesswrong.com/posts/75dnjiD8kv2khe9eQ/measuring-...

In that scenario, you can go from 0 independent artificial intelligences to tens of millions of them, very quickly.

sbierwagenon Which power plant does my electricity come from?

There are "many" places where people would pay US$200 to run an air conditioner for one hour?

sbierwagenon The size of BYD's factory

Not entirely correct. Boeing, despite all the bad press, actually reversed course on this recently. 787's wing was made by a supplier, but 777X's wing is actually built in-house, right next to the main factory, starting from carbon fiber fabric.

sbierwagenon AlphaProof's Greatest Hits

More information about the language used in the proofs: https://en.wikipedia.org/wiki/Lean_(proof_assistant)

sbierwagenon Unusual Raku Features

The greatest trick the Devil ever played was renaming Perl 6 to Raku.

sbierwagenon Cops suspect iOS 18 iPhones are communicating to force reboots

Apple calls this Activation Lock: https://support.apple.com/en-us/108794 https://support.apple.com/en-us/120610

Obviously, the logic board is locked to the owner's Apple account, but so is the display, battery, camera, and selfie camera. Basically the only thing you can reuse is the metal frame of the phone.

Phones are still stolen (since the cost of theft is $0) but stolen phones are worth closer to $5 than $1000.

sbierwagenon SimpleQA

>But will this ever be possible by an LLM?

Why not? Just train an unbelievably gigantic LLM that encodes all human knowledge. A hundred trillion parameters ought to do it.

sbierwagenon SimpleQA

https://openaipublic.blob.core.windows.net/simple-evals/simp...

The steps I took to find this link:

1) Look at simpleqa_eval.py. See that it loads "az://openaipublic/simple-evals/simple_qa_test_set.csv" Hmm, some weird vendored protocol.

2) I don't feel like digging through bf.BlobFile() to figure out how it downloads files and I certainly don't want to generate an API key. Cross fingers and do a Bing web search for "az://openaipublic"

3) That leads me to https://stackoverflow.com/questions/76106366/how-to-use-tikt... Ah ha, this answer has the link https://openaipublic.blob.core.windows.net/encodings/cl100k_... which automatically downloads a file.

4) Poke the relevant parts of the az:// link into this link, and a csv appears.

sbierwagenon Quantized Llama models with increased speed and a reduced memory footprint

One of the fun things about signals theory is how the same basic concept will show up in apparently unrelated places.

Example from electrical engineering: microprocessors will have a "clock" frequency, say, 16Mhz. But when you haul a wire up to VCC and pull it back down to ground, some amount of the power will be radiated away as radio waves. If your clock is at a constant rate, then you'll have a big spike of radiated noise at 16MHz, and the FCC will be unhappy.

So modern devices cheat it by dithering around the central frequency. If you bounce from 15.9998MHz to 16.001 to 15.998 then the same amount of power will be radiated, but smeared across a bigger frequency, enough to get you lower than the regulatory threshold. Spread spectrum clock generation. https://www.analog.com/en/resources/technical-articles/clock...

If you look in your PC's BIOS settings, spread spectrum is usually an option, and you can disable it if you want your computer to be slightly noisier.

sbierwagenon First images from Euclid are in

Parallax shift from the spacecraft moving along its orbit isn't measurable past 16,000 light years. The Milky Way is about 100,000 light years in diameter, so for most of the stars in our galaxy, let alone extragalactic objects, there's no effect.

For closer objects this shift is useful, as it's the only way to directly measure the distance to a object: https://en.wikipedia.org/wiki/Parallax_in_astronomy Every other method for estimating distances to astronomical objects (standard candles, redshift, etc) are based on parallax measurements.

sbierwagenon Boeing, Union reach wage deal to end strike

>Presumably they lost one month of pay.

A new grade 4 hourly worker at Boeing made $19 an hour before the strike. $3,040 a month before taxes. https://www.iam751.org/docs/2024/FRONTMar24.pdf

There's a reason they went on strike. $36,480 a year doesn't go far when you have to pay Seattle area rent.

sbierwagenon A solar gravitational lens will be humanity's most powerful telescope (2022)

Protector by Larry Niven (1973) also features a gravity-powered telescope.

sbierwagenon A Cheap, Low-Tech Solution for Storing Carbon? Researchers Suggest Burying Wood

To turn trees into lumber you have to cut them down, transport them to a sawmill, cut them to size, kiln dry them, transport them to the build site, build a house out of it, etc.

Underground sequestration has no transport, milling or kiln costs. Just cut down a bunch of trees, dig a trench where the trees used to be, and bury the trunks.