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Cake day: February 1st, 2024

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  • Prescriptive vs. descriptive is different in colloquial language than in science.

    If my data logger captures 1kB/km, how many bytes/meter is that? In every other quantitative unit I can think of, the k should cancel out; but if you want computers to be special, that’s your preference.

    Metric sucks. Powers of ten are arbitrary, a fluke of biology. Powers of two are the only sensible way to make a system of measurements.

    Then why are you trying to shoehorn binary into decimal? As in: why are you using decimal prefixes in the first place? Answer is probably that most people have intuition behind powers of ten. You can easily express in log2-bytes instead (a GiB is 30, a TiB is 33…etc.). Be the change you want to see!

    I’m born and raised in the USA, and while imperial units can be handy for a few every day tasks, there’s a reason why the sciences in the US tend to use metric.

    Regarding cooking, I’ll stick to metric, measured by weight. I can double, halve, or multiply my recipe by pi, and all I have to do is look for a different number on my scale.


  • Giga, Mega, Kilo…these are all SI prefixes; they differ by a factor of one thousand, which is very clean in base ten.

    Ten in binary systems isn’t special, but two is; and two to the ten is very nearly a thousand, and a thousand separates the major SI prefixes. This is a neat coincidence, but should not IMHO change the meaning of the prefix.

    Metric units are awesome in large part because of the use of prefixes; messing up the meaning of prefixes is a disservice to the SI/metric system. Giga == billion independent of the context. A light-year is close to 10 petameters, but no one would claim it’s exactly 10Pm.

    Now, if you want to call it an “imperial gigabyte,” by all means…




  • I do something similar — I have a raspberry pi and a HD, with daily rsync and snapshots (monthly retained indefinitely, weekly retained for a month, daily retained for a week). It’s at family’s house, connected to my home via WireGuard via a VPS. Tailscale (or anything really) would also work here.

    It’s a great setup! Just have some watchdog reboot if it can’t talk to home (a simple cronjob with ping -c1 home.lan || reboot or similar).

    Even our “slow” 35Mbps upload speed is way more than enough for incremental rsyncs of my Immich library. The initial sync was done in person, though.












  • Aluminum foil is very common in physics labs. And a main use for it is “baking”! To get ultra high vacuum (UHV)* you generally need to “bake out” your chamber while you pump down. Foil is used same as with baking food — keep the heat in and evenly distributed on the chamber.

    Sadly, it’s usually not food grade aluminum foil, as that can contain oils, and oils and vacuum are generally a big no-no.

    *Just how good is UHV? Roughly: I live in San Francisco, which is ~7 miles by ~7 miles (~11km). Imagine you raise that by another 7 miles to make a cube. Now, evacuate every last molecule of gas out of it. Now take a family sedan’s trunk, fill it with 1 atmosphere of gas, and release that into the 7 mile cube. That’s roughly UHV pressure.