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Joined 11 months ago
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Cake day: August 9th, 2023

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  • I think we can put a specific maximum for a comfortable western lifestyle. You can certainly argue that a comfortable western lifestyle is already far and away better than most of the people on Earth will ever see. This is something of an arbitrary point where past this, most of us are going to agree that it’s excessive.

    It’s USD 10 million.

    Why? Let’s start with the Trinity study:

    https://thepoorswiss.com/updated-trinity-study/

    The original looked at a standard retirement portfolio and asked how much you can withdraw over a thirty year retirement. It took market data from 1925 through 1995 (the updated version linked above goes to 2023) and then checked a thirty year window over that entire period with various withdrawal rates.

    What it found is that if you withdraw 4% of the portfolio the first year, and increasing it by inflation each subsequent year, it’s highly unlikely the portfolio will run out in the 30 year window. The time period covers has market ups and downs, high inflation and low, and this 4% stays.

    The updated study above says a 3.5% withdraw had a high chance of lasting 50 years.

    Lets play it ultra safe and put it at 2.5%. With $10M, we’ll have $250,000/year to play with, and our rules adjust that for inflation.

    (Median household income in Manhattan is $128k)[https://www.point2homes.com/US/Neighborhood/NY/Manhattan-Demographics.html]. We’re pulling almost twice that. I feel comfortable saying a person can live nicely in any city on this income.

    So there you go: $10M. If you want a 100% tax bracket, that’s a good place to put it. Any more money past that is just a game that hurts everyone else.










  • I’d like to take this opportunity to highlight a recent discovery that I think should be shouted from every major news outlet. The implications are big, but they’re rather technical and non obvious.

    https://www.youtube.com/watch?v=B1PbNTYU0GQ

    In short, it turns out water evaporates much faster from to light than heat. Green light with a certain polarization hitting the water surface at a 45 degree angle seems to do best. From the research slides, the effects of polarization and angle might be small. That means green LEDs (which are cheap and very efficient, but wouldn’t be polarized on their own) can evaporate lots of water. Something like 4 times the amount we would get from using the same amount of energy to heat it up. This is being called the photomolecular effect.

    This fills in a big gap in our climate models. There have been measurements done on clouds that show water was evaporating much faster than theory would predict. I’m not clear on if it would make the results more pessimistic or not. My guess is that more clouds in the model increase the albedo of the Earth, thus reflecting more light back into space, and the resulting temperature should be lower. But I’ll hold off on strong opinions until the models get updated.

    The other big thing is desalination. Most desalination plants don’t use thermal evaporation because it’s too energy intensive. They use reverse osmosis. The photomolecular effect brings up the possibility of an even more efficient solution to drinking water problems.

    I haven’t seen academic research into this yet, but I also wonder about the implications for lithium extraction from sea water (and pretty much any other sources, really). Lithium is basically one of the salts you remove during the desalination process, so the photomolecular effect potentially makes sea water extraction cheaper. Lithium from sea water is an indefinite resource–there’s more there than we would know what to do with.







  • As an example, Klipper (for running 3d printers) can update its configuration file directly when doing certain automatic calibration processes. The z-offset for between a BLtouch bed sensor and the head, for example. If you were to save it, you might end up with something like this:

    [bltouch]
    z_offset: 3.020
    ...
    #*# <---------------------- SAVE_CONFIG ---------------------->
    #*# DO NOT EDIT THIS BLOCK OR BELOW. The contents are auto-generated.
    #*#
    [bltouch]
    z_offset: 2.950
    

    Thus overriding the value that had been set before, but now you have two entries for the same thing. (IIRC, Klipper does comment out the original value, as well.)

    What I’d want is an interface where you can modify in place without these silly save blocks. For example:

    let conf = get_config()
    conf.set( 'bltouch.z_offset', 2.950 )
    conf.add_comment_after( 'bltouch.z_offset', 'Automatically generated' )
    conf.save_config()
    

    Since we’re declaratively telling the library what to modify, it can maintain the AST of the original with whitespace and comments. Only the new value changes when it’s written out again, with a comment for that specific line.

    Binary config formats, like the Windows Registry, almost have to use an interface like this. It’s their one advantage over text file configs, but it doesn’t have to be. We’re just too lazy to bother.