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matthewdgreen

12,995 karma · joined August 19, 2012

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matthewdgreen··on Toyota’s hydrogen-powered Mirai has experienced rapid depreciation
H2 from electrolysis is wildly expensive. H2 from natural gas is more affordable. Both are alternatives to BEVs, which are the better approach to electrifying transport. If Toyota had gone all in on BEVs when it began its H2 strategy, it would be selling more EVs than Tesla. Instead it entirely ceded the field to others, first Tesla and BYD.
matthewdgreen··on Why Is the American Diet So Deadly? (2025)
Don’t forget adding all the artificial emulsifiers, which impact the intestinal lining.
matthewdgreen··on Without America to rely on, EU gearing up to be a global power in its own right
It's been the goal of several administrations for the EU to increase spending, and the lip service goal of this one. But I don't think anyone really wanted the EU to stop purchasing US weapons or abandon the very useful economic/military dependencies that benefited the US. This administration appears to have pushed hard enough to actually break those ties, and I don't think they (and their supporters) fully appreciate how bad that could be.
matthewdgreen··on The risk of a hothouse Earth trajectory
We’re not disagreeing. I’m saying that the tax should be set high enough that it creates the desired behavior, which is to disincentivize the widespread use of polluting plastic bags AND/OR ensure that they’re recycled and don’t wind up in the environment. If you’re charging $.05 per bag and people are just eating the tax and the bags are winding up in wetlands in similar amounts, that means your tax regime isn’t effective. You should either increase the tax or improve the system. My city’s absolute ban is equivalent to setting the tax to infinity, which is one solution that seems to work well.
matthewdgreen··on The risk of a hothouse Earth trajectory
Exactly. The point of this sort of tax should not be to collect revenue, it should be to ensure that non-biodegradable bags are being disposed of correctly. To the extent that this is not happening, any bag tax is malfunctioning. Such a tax is either insufficient or poorly-designed. (Our city just banned chain stores from giving out plastic bags under 4 mils thick, and stores now give out paper and sell re-usable bags.)
matthewdgreen··on The risk of a hothouse Earth trajectory
Many cities have banned plastic bags, and the results have been miraculous for waterways and wetlands. It turns out that shore animals don't benefit as much from "hope a few customers choose the better thing, but otherwise let them take home single-use crap that immediately blows off into natural settings."

https://www.nytimes.com/2025/06/19/climate/plastic-bag-bans-...

matthewdgreen··on The risk of a hothouse Earth trajectory
We contribute to it 1% by the actions we take as individuals, and 99% by the leaders we select.
matthewdgreen··on Gallup will no longer measure presidential approval after 88 years
Because there's a good chance it does have something to do with Trump? Gallup has Federal contracts, which means that a vindictive administration could potentially hold them hostage for reporting bad approval numbers. Eliminating their famous (yet inconvenient) poll removes that threat. This is more or less why the Washington Post is being destroyed, as well.

The company's own explanation is a pile of Gish gallop.

matthewdgreen··on The US is flirting with its first-ever population decline
Not sure how old they are, but we found that this loneliness phase got better once they were in school (and better as they got into middle, then high school.)
matthewdgreen··on Experts Have World Models. LLMs Have Word Models
To be clear, GP is proposing that we live in a society where LLMs will explicitly censor scientific results that are valid but unpopular. It's an incredibly strong claim. The Hooven story is a mess, but I don't see anything like that in there.
matthewdgreen··on Experts Have World Models. LLMs Have Word Models
Aside from a few friends, are there any good writeups of this? Surely someone is documenting it.
matthewdgreen··on Experts Have World Models. LLMs Have Word Models
There’s a lot of concern on the Internet about objective scientific truths being censored. I don’t see too many cases where this is the case in our world so far, outside of what I can politely call “race science.” Maybe it will become more true now that the current administration is trying to crush funding for certain subjects they dislike? Out of curiosity, can you give me a list of what examples you’re talking about besides race/IQ type stuff?
matthewdgreen··on The time I didn't meet Jeffrey Epstein
As far back as 2008 a quick Google for Epstein's name would reveal Wikipedia and mainstream news outlining the charges. He was convicted for soliciting a 14 year old, but the charges covered many other girls and sexual assaults.
matthewdgreen··on Data centers in space makes no sense
The whole AI bubble makes way more sense if you model it not as rational economic activity, but rather as the actions of a rogue AI slowly taking over our institutions and redirecting them towards its goals. Data centers in space make no sense economically, but think of how survivable the rogue AI will be once we build those orbiting data centers! (I am joking about this, but it's weird that my logic makes sense.)
matthewdgreen··on Court orders restart of all US offshore wind power construction
Is he working in concert with the current administration on this issue? That's going to be the question with many of these new tech-billionaire/administration collaborations.
matthewdgreen··on Euro firms must ditch Uncle Sam's clouds and go EU-native
Well, at the early stages, yes. But at the point where incumbent tech firms have an insurmountable advantage, just adding more startups probably isn't going to save you. Entrenched providers can use their market power to buy up/outcompete/destroy any smaller competitors. You really need both a native market and a startup scene.
matthewdgreen··on US has investigated claims WhatsApp chats aren't private
I really doubt this. Any such upload would be visible inside the WhatsApp application, which would make it the world's most exciting (and relatively straightforward) RE project. You can even start with a Java app, so it's extra easy.
matthewdgreen··on I stopped following the news
In October 2024 I would not have guessed that we'd ever see masked agents killing people on the streets of major US cities, or the US administration immediately accusing the victims of being armed terrorists. Things can change rapidly. By allowing things to get this bad, we have unfortunately forfeited our right to pretend things can't change rapidly. Let's plug in; fix this situation; and then folks can go back to ignoring the news.
matthewdgreen··on I stopped following the news
Some topics can't be ignored. Vaccine effectiveness, for example, require a consensus from a large fraction of the population. That larger societal consensus begins with discussion in smaller subsets, of which HN is one.
matthewdgreen··on Tesla ending Models S and X production
The original argument was that Tesla made a substantial amount of its revenue from subsidization, i.e., government mandated payments extracting money from one set of people to fund another. Subsidies can entail direct taxation, followed by payment to a company. Alternatively, they revolve around regulatory schemes that mandate transfer payments from one group (in this case, ICE car manufacturers and their customers) to another (EV manufacturers.) Although the mechanism is slightly different, they're both subsidies. To be clear: I have no problem with these subsidies! Just think your pedantry is misfiring.
matthewdgreen··on Amazon One palm authentication discontinued
I've consciously reduced my pocket contents from car keys+wallet+phone to driver's license+phone. I'd love to be able to get rid of the phone sometimes.
matthewdgreen··on Amazon One palm authentication discontinued
I don't want Amazon to own my palm print, but I also love using weird payment technology. So I would have probably been dumb enough to sign up at Whole Foods if I'd noticed that was an option.
matthewdgreen··on FBI is investigating Minnesota Signal chats tracking ICE
I mostly focused on the cryptographic parts of the files. Here's what I wrote after the first details of cryptographic attacks were released: https://blog.cryptographyengineering.com/2013/09/06/on-nsa/

What I learned in that revelation was that the NSA was deliberately tampering with the design of products and standards to make them more vulnerable to NOBUS decryption. This surprised everyone I knew at the time, because we (perhaps naively) thought this was out of bounds. Google "SIGINT Enabling" and "Bullrun".

But there were many other revelations demonstrating large scale surveillance. One we saw involved monitoring the Google infra by tapping inter-DC fiber connections after SSL was added. Google MUSCULAR, or "SSL added and removed here". We also saw projects to tap unencrypted messaging services and read every message sent. This was "surprising" because it was indiscriminate and large-scale. No doubt these projects (over a decade old) have accelerated in the meantime.

matthewdgreen··on White House alters arrest photo of ICE protester, says "the memes will continue"
There are people on this site who will still turn out to vote for this administration and their allies in Congress. It's wild.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
At that point, who really cares? As scale goes down and economies of scale go away, it just becomes an irrelevant novelty. But the actual question is: how much will industrial applications matter.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
That's more or less what heat pump clothes dryers do. They draw in air, heat it, and then blow the humid air back over the cold side of the heat pump loop to condense it. They save tons of energy. I don't think there's anything similar for water (in clothes or dish washers) but the quantities might just be too small to bother with.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
A typical dishwasher load requires 1-3kWh, so you'll just use your home battery and do it whenever you want.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
Seems unlikely that we'll be selling oil for $5, unless fossil fuels are completely replaced and it becomes a side-of-the-road novelty.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
Most rooftop install costs are labor. The PV is now a minimal slice of it. Which is why mandating solar on new construction is such an important policy: don't make two sets of laborers clamber around the same roof.
matthewdgreen··on In Europe, wind and solar overtake fossil fuels
If you're a renter/condo then you're probably getting excess solar generation delivered to you from homeowners with nearby solar roofs. So presumably there is some benefit to you in terms of cheap generation.
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