• 22 Posts
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Joined 2 years ago
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Cake day: June 12th, 2023

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  • It was the mid-90s, and just a shell account. Gopher, archie, pine and zmodem.

    We didn’t get PPP access for a year or two; this was the days before google - yahoo, altavista, some other engines I can’t remember, and metasearch engines like dogpile that would query a bunch of different search engines and return the combined set of results.

    This was the days of mailing lists and usenet for the most part - connect up, download messages for like an hour, then log off, read and reply, then log on and send.

    I was there for the original hamsterdance, and it ruled.





  • Individual oxygen atoms are very very grabby; they’re stage-5 clingers on PCP. They’re straight-up homewreckers, and they cannot and fucking will not be alone. They need a friend or two, and they will go and rip molecules apart to take them because fuck you.

    Now, if there’s nothing else available, they’ll pair up with another oxygen atom, and form O2, what people normally call oxygen; the stuff you find in the air.

    But it’s an uneasy alliance, and the bond angles are all wrong so it’s kind of spring-loaded.

    And the same goes for lots of other molecules - carbon-carbon or carbon-hydrogen bonds ferinstance are also kind of tense and uncomfortable; it takes a surprising amount of energy to snap them into place, like building a tower of interlocking mousetraps.

    So smack an O2 at reasonably high speed (or in other words, at a high temperature) at big structure of carbons and hydrogens, and it’s fucking chaos.

    The oxygen-oxygen bond splits, and the two halves grab the other atoms, ripping the structure apart and releasing all the energy that went into spring-loading those bonds.

    The main byproducts are CO2 (a carbon with two oxygens) and H2O (an oxygen with two hydrogens), both of which are very low-energy, strong bonds.

    They’re both gases, and all that energy leftover is released as heat, which does two things:

    • raise the temperature enough to do the same thing with even more O2s, causing a chain reaction
    • heat up the released gases (and any bits of random gunk that break off with them) so much that they glow red hot, just like hot iron.

    So you get plumes of glowing hot gas-and-particles streaming off the stuff that’s burning - and hot air rises, so the plumes point upwards.

    But they also cool down quickly in the air, below the glowing-hot point, and that’s why flame has a shape: the boundary is how far as they get while still hot enough to glow.

    Of course, hydrocarbons and carbohydrates aren’t the only things that burn, there’s lots of other molecules you can do this to, and the same principle applies. It’s just that carbony things tend to burn easily and well, and we’re surrounded by the stuff because that’s what living things are made of, so that’s what you tend to see being on fire the most.



  • Humans are horribly, miserably energy efficient.

    Seriously we evolved as exhaustion predators: pick an animal and just keep walking after it until it drops, then eat it. That’s our whole schtick. We are the goddamn terminator.

    Just being alive and breathing uses up about 1500-2000 calories a day.

    An absolute bastard of a workout will use up maybe 100 on top of that, which makes up for like a spoonful of peanut butter.

    As such, you can’t practically lose weight via exercise alone. You need to bring calories-in down to less than calories-out.

    The tricky part is doing it in a controlled and sustainable manner so you don’t just say fuck it and scarf down two whole pizzas for lunch in a week’s time because you’re hangry and don’t care any more.