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AlanSE

547 karma · joined February 6, 2014

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AlanSE··on Is Power from Pure Proton Fusion Possible?
This is my personal version of AI solving an advanced math problem.

I'm into deep future concepts, and have always dreamed about this sci-fi kind of open question. I will tell you that it is categorically not possible until the Opus or Sol level.

It took a few tries, but it has now returned to me a result that gives fuel cycle closure for this problem. That's a big deal to me.

What the heck is this problem? Imagine that the year is 2150 AD, and you are running out of Deuterium you harvest from the upper atmosphere of Saturn. Options like Helium-3 from the moon are far too small in abundance. If you can directly get energy from proton fusion, you are master of the Milky Way. The mechanism to do that is well-know, you fuse protons into Carbon, Nitrogen, Oxygen isotopes like how a star does it. But can you do it outside of a star? This idea (original AFAIK), is to use Deuterium mixed with other fluids in the fuel cycle (15N) to compress the target in a multi-stage thermonuclear detonation. There are a lot of problems, but the main that makes this "not impossible" is: can you do this and still produce surplus isotopes for the pusher fuel? On the speculative level, answer is "yes". This comes with a specific scale, which is a fuel ball <500 meters, blast chamber size of Earth. Room for improvement, but a great start.

This is a ferocious problem. It's a pleasure to be able to run the numbers on it.

AlanSE··on AI to hit almost 40% of jobs worldwide
Site won't connect with https, this works for me.

http://www.econ.yale.edu/smith/econ116a/keynes1.pdf

AlanSE··on A half-hour to learn Rust (2020)
Can someone explain to me where the feeling_lucky variables comes from in the match example? I don't get it. The variable isn't defined anywhere in the relevant scope.
AlanSE··on Water Cooled Rooftop Solar Panels
> For the same reason, the enthusiasm for the idea of installing solar plants in north africa and exporting power over interconnectors to Europe is gone. It's cheaper to install twice as many panels in a field in cloudy northern Europe (where capacity factors are half of what they would be in the Sahara) than deal with the costs and complexity of underwater interconnectors and transmission system upgrades.

I don't know about that, because long-range transmission significantly reduces the intermittency, even for the same longitude. It's not just about smoothing out the curve of solar production, demand patterns (due to weather, industry, behavior) will also have variations from place-to-place and these allow opportunities for power export.

Some places will have more dispatchable and expensive power plants than others, which also creates an export opportunity so that power is exported so that one country can burn less fuel. However, I admit this argument is slightly undercut by the question "can't we just build solar panels in the country with dispatchable dirty power?" True, but there's also a connection to wind power which is super local and random.

AlanSE··on A room-temperature superconductor? New developments
It's still not believed. It's just Twitter that I've seen the juicy stuff, like a (very sketchy) claimed replication from a Russian, and now another claim from a Chinese group.

I could still see this being something "new" but not a true superconductor. If you read the link, there seems to be some kind of discovery brewing, but the original discovers may not have understood what they found.

AlanSE··on A room-temperature superconductor? New developments
No no no, this eliminates the need for cryo, not crypto.
AlanSE··on A room-temperature superconductor? New developments
Fusion was already starting to heat up in recent years. The entire SPARC reactor concept is based on (low-temp) superconductor materials breakthroughs.

If these room-temp superconductors pan out, it will be dumping gasoline on the funding fire for new fusion attempts. Given less than a year from scientific verification, fusion will go red hot.

AlanSE··on How too much daydreaming affected me
The ideal conditions to stimulate daydreaming seems pretty obvious to me - sit me down in any class lecture.

Imagine that my mind like a glider. Glider is connected to a Cessna by a tether, but it's a magical tether that can disappear. In fact, it takes me active work to keep it connected, like I'm holding on to the end of the rope with my hands. The plane takes off and I'm following in lockstep about the main subject matter... looking down at the landscape below, to the left, to the right. After a quick climb, and at velocity, I've forgotten about keeping tethered, holy crud, I'm in the air! I want to bank, dive, maybe loop! What's over here? I can catch a thermal and go on forever depending on the landscape, but still often see more appealing currents and need to switch over. Oh wait, where did the plane go?

AlanSE··on Attention Is Off By One
Yeah, good to bring it back to the original point. Reading the article felt exciting, but in hindsight I am now missing a key detail.

The equations all seem to be matrix operations with a fixed number of rows / columns (you can take me as a real layman here). Unless you change that, I don't understand _how_ you can reduce memory needs. Granted, I'm probably putting my foot in my mouth not understanding transformers.

AlanSE··on Cash Amnesia
Yes, I should have Googled that before using the wrong word.

I am also operating on old information, perhaps the law changed and this it varies by state now.

AlanSE··on Cash Amnesia
As in, they use tax to avoid reporting the earnings? That works fine for the scale of a lemonade stand.
AlanSE··on Cash Amnesia
Higher cash prices are a violation of the card-holder agreement.
AlanSE··on The force that shapes everything around us: Parking
In fact, I have increasingly seen the pattern of adults who work from home but have a commute to drive their children in the morning / afternoon. That's 2-ways both times, for the record. It's often multi-destination.
AlanSE··on The force that shapes everything around us: Parking
I hope/believe that we are near a tipping point. There is a very large and very substantial neighborhood premium based on what's around it, but the zoning is the same everywhere so the competition was legally restricted to greenways, sidewalks, parks, and HOA facilities. Even in the suburban US, it is a VERY desirable feature to be within walking distance of a park where young children can play. This has created a strange effect, where people (let's be honest, affluent people) accumulate a collection of aspirational wheeled items - strollers, bikes, weird electric skateboard-like things, and other wheeled things for the kids. These are coupled local government parks and spaces where people can ride a bike JUST FOR FUN. I mean it very seriously that greenways outright avoid any turns that might be useful for economic life. Riding bikes on the roads is mostly for the true anti-car zealots.

I've been ready to buy a house for few years, but I've realized I'm no longer happy with the whole package. I want to realistically be able to walk or bike to get a dinner, coffee, or groceries. Yet, city centers (in the south for sure) tend to offer the most dangerous roads for doing this, and unhealthy environment, and poor social atmosphere.

I'm sensing that there are more people on the sidelines (who have remove jobs, after all) who are ready to buy into better neighborhoods. These people may not be willing to give up their cars, but there is negotiating space, and it is relevant that these are people who have economic clout to force the issue.

AlanSE··on Solar energy solves global warming
I've been following Terraform Industries for a while, and it does strike me as obvious that H2 will be the preferred form of energy storage medium in the long run, not just an intermediate species.

Depending on the conditions, if you're doing day-night energy storage, then you would like to fill up the H2 tank and then burn it when demand ramps up.

The only role I see for methane is when your H2 tank is already filled up but your solar panels are still producing. This is not just possible, but deterministically required whenever solar gets deployed enough for seasonal storage to be necessary.

Right now California is something like 35% solar + wind energy, and the "duck curve" is nearly maxing out. This was predicted in extreme specificity 20 years ago, as >30% and you get stuff like zeroed-out energy prices during the day. We have not solved the day-night (daily) energy storage problem, which only requires storing energy for a matter of hours.

When you go to something like 60% renewables, then even crazier stuff happens. Overproduction during sunny times goes bananas and (assuming daily storage is solved, which it isn't) seasonal issues start to arise. I don't think H2 will ever work for seasonal storage, although I think it's fine for multi-day storage scenarios. It's not theoretically impossible, I just compare to the equivalent that we have for natural gas and realize you would need MANY TIMES that level of investment to save the same amount of energy in H2. Plus, fossil fuel gas producers are mostly at a constant level, whereas solar production outright needs summer-to-winter storage.

What I don't buy is that these units will be disconnected from the grid and be economical by their gas products. No way, no how. What you want is to run the chemicals plant with low-voltage solar power locally, and trade-off with the grid as is economical.

AlanSE··on PhotoPrism: AI-powered photos app for the decentralized web
I tried this about a year ago and it was alright. I wanted to like Photonix, as it was a python library and I expected would be easier to hack, but I couldn't lie to myself. PhotoPrism is very clearly and very obviously the most mature of the available projects for this.
AlanSE··on The underground economy of Glassdoor reviews
So is it basically true that there is no objective information out there anymore, because anyone running a successful site gets corrupted with money?
AlanSE··on A reason for high housing prices: restrictive land-use regulations
Also, builders want to build high-margin houses, not low-margin houses. Also, high-margin housing gets advertised, low-margin housing does not.
AlanSE··on A reason for high housing prices: restrictive land-use regulations
They see new builds hitting the market and look at the (aspirational) price put there by the builder. It's a borderline conspiracy that Zillow lists certain high-end new developments for a year (before they're built) which pollutes the "for sale" housing inventory. Whereas the "recently sold" is the best metric of how things actually are, the search options don't allow you to get an accurate market sense from these. After all, the app's purpose is not to give you an accurate sense of the market.
AlanSE··on USGS estimates at least 45% of U.S. tap water contain forever chemicals
I have been, personally, figuring that I should wear mostly cotton clothing and glass / ceramic (as opposed to plastic) dishware. Limiting material choices for household items would be politically impossible, but I would like it to become a popularized "trend", which retailers will then cater to.

Companies should market based on using "traditional" non-toxic materials (still modern and industrial, just not absurd), and consumers can respond by giving their business.

AlanSE··on USGS estimates at least 45% of U.S. tap water contain forever chemicals
Maybe get rid of them in clothes and personal care products at least?
AlanSE··on USGS estimates at least 45% of U.S. tap water contain forever chemicals
It needs to be more expensive to hire lawyers (and lobbyists) than to hire engineers to solve the problem. Some companies will fail to adapt and continue to fight legally in lieu of adding filters and complying, and those companies should get shut down.
AlanSE··on USGS estimates at least 45% of U.S. tap water contain forever chemicals
I clicked on a few data links from the paper... not ideal, but you take some of the identifiers, Google for them, adjust the criteria a bit...

https://ncpfastnetwork.com/data

And that's what you're asking for, but for the state of NC. I presume a similar path can be taken for other states.

This allows basically going "I live in XYZ city, so my total PFAS is 50 ppt". What you do with that information is unclear. Share on Facebook?

AlanSE··on USGS estimates at least 45% of U.S. tap water contain forever chemicals
Not trying to be the troll, but this debate is missing the obvious retort.

> Why aren't we forcing the polluters to pay for the cleanup

Because then the manufacturing goes to China. It doesn't get cleaner, it might actually get worse. The pollution goes somewhere else. Economic anxiety (which is politically explosive, see 2016 election) goes up domestically.

What we need is effective regulation, not bureaucratic us-versus-them regulation. We need more engineering spending and less legal spending. And as a consequence, yes, we need fewer choices in consumer products and higher prices, and we need consumer safety laws that prevent offshoring from undermining all of that.

AlanSE··on Have you been to the library lately?
I honestly, genuinely, fail to understand the meaning of that. It can't possibly be true that homeless people didn't exist before the 1980s. What does this actually mean?
AlanSE··on Have you been to the library lately?
What town is that? As I go through my life experiences, every affluent place I've lived in my state, NC, has had decent libraries. They are used mostly by kids and old people, anecdotally.

I laughed on the inside a bit when I considered the fact that a public library existed just a few blocks down from the library of a large public university. But this was my youthful ignorance. Anyone could walk in the university library and open a book (well, you could at that time, not so sure about anymore) but you had to have a school ID card to check out a book or access the computer system.

Before cell phones, I visited libraries traveling around the coast. The computers were 100% taken. There was a line to get one, and the librarian directed us to a scheduling system. These were people who needed to use a computer and the internet to apply to a job. Access was scarce, low-quality, and competency to use those tools were lacking.

Nowadays, cell phones have mostly taken away that niche of the past. I'm not sure if or why the people there still need the libraries.

AlanSE··on Drone cops are coming for small-town America
From a technical standpoint it doesn't make a lot of sense.

CCTVs in cities are a big political topic. For corridors that people walk through often, this is much more effective for facial recognition and you don't have to power propellers or deal with crashes. The camera will operate for a decade without incident.

For overhead algorithmic surveillance, just use satellite photos. I fully expect that sat swarms in LEO surveillance will become a thing in my lifetime. Sure there are clouds, but the whole thing is imperfect, the goal isn't to track you 100% of the time and they don't need to anyway.

For persistent surveillance, drones are good for what exactly? Periodically peeking in windows? How many windows would a drone need to look in on a patrol? Can you fly them low enough to actually do this? On a regular route at that, my god.

I'm very worried about tracking with facial recognition and systematic location collecting based on cell signals and satellite car tracking. But this article was about a drone catching people smoking weed after a busybody called 911. The tech is a very marginal sideshow in that story.

AlanSE··on Drone cops are coming for small-town America
Getting a camera 400 feet in the air after a call to 911 dispatch gave a location sounds like a perfectly-balanced fulfillment of the social contract.

While there is an abundance of creeping excesses with tech and policing, the slippery slope argument got completely lost here.

AlanSE··on Parents in Ireland town to voluntarily ban smartphones for kids as old as 13
I strongly agree with almost everything I've read here, but I agree less-so that screen size doesn't matter.

We don't build computers to be used socially. I've seen... demos? Someone makes a table with touch input recognizing the entire space and installs an app that encourages collaborative investigation. This is a far cry from an app. If I were to go through a list of all tech developments in the last 10 years, I can't imagine more than 2 or 3 that did something to improve IO-level collaboration. We have LOTS of collaboration software, but none of it is on the human-interface level. You start with everyone having their own device.

Big screens are good IMO. The bigger the better, take the entire wall. One room should have 1 screen. It should be so big and unignorable that people stop taking the personal screen they carry in their pocket.

I know all the shows that my other family members watch. I don't love 'em, but I can have a conversation about a character (and we do!). On the other hand, I have no accurate sense what TikToks they watch. Yet, those TikTocks have been dramatically more impactful of people's views on various subjects from politics, to cleaning, to finance, to mental health. But there's no opportunity to say "hey, that's false".

AlanSE··on Against longtermism (2021)
Or any philosophy, for that matter. I have been reading up on this subject, "What We Owe The Future" book lately. As I soak up more of the arguments, I see a lot of spilled ink, highly debatable key takeaways, and no practical recommendations for actions which were not already obvious.

In other words, the same thing you will get from any moral philosophy class. If you start philosophy expecting to get something tangibly productive... you are in for a disappointment.

For me, I think the important grain of salt is that better moral accuracy provides little to no value. You or I can do more good for the world with greater effort, but the efficacy of that good is mainly based on the real opportunities which we are connected to through the course of our actual lives. Different moral compasses would give slightly different answers, but the optimization makes a vanishingly thin difference. There was never much doubt about what was needed to be a better person, it's just self-interest and vices, which are completely known quantities, that keeps us from it. The exact flavor of utilitarianism under the hood is pretty much irrelevant.

I do find some value for philosophy as a thought exercise that allows us to entertain radical thought experiments far from the mainstream (see internet trolley cart memes). However, as I see longtermism now, it's pretty vanilla.

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