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Cake day: February 1st, 2024

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  • That’s…not really a cogent argument.

    Satellites connect to ground using radio/microwave (or even laser), all of which are electromagnetic radiation and travel at the speed of light (in vacuum).

    Light in a fiber travels much more slowly than in vacuum — light in fiber travels at around 67% the speed of light in vacuum (depends on the fiber). In contrast, signals through cat7 twisted pair (Ethernet) can be north of 75%, and coaxial cable can be north of 80% (even higher for air dielectric). Note that these are all carrying electromagnetic waves, they’re just a) not in free space and b) generally not optical frequency, so we don’t call them light, but they are still governed by the same equations and limitations.

    If you want to get signals from point A to point B fastest (lowest latency), you don’t use fiber, you probably use microwaves: https://arstechnica.com/information-technology/2016/11/private-microwave-networks-financial-hft/

    Finally, the reason fiber is so good is complicated, but has to do with the fact that “physics bandwidth” tends to care about fractional bandwidth (“delta frequency divided by frequency”), whereas “information bandwidth” cares about absolute bandwidth (“delta frequency”), all else being equal (looking at you, SNR). Fiber uses optical frequencies, which can be hundreds of THz — so a tiny fractional bandwidth is a huge absolute bandwidth.





  • It is really powerful per watt, and has a built-in UPS. Any homelab type things you could do with that? macOS+homebrew will give you a nice *NIX feel, very familiar if you’re a Linux user.

    I’m a fan of having a remote homelab computer+disk for off-site storage. This would be a good candidate in that it wouldn’t use excessive power at a friend/family’s place, but may be overkill (I use a pi3 for that).













  • Yes. But why is there an absence of light?

    If there are infinite stars, then every direction you look would encounter a star. (Things stay the same brightness per subtended angle as they get far away. Space dust doesn’t matter, as it would thermalize and radiate.)

    So, the universe can’t have infinite luminous matter, be static and ageless, because if it were then the night sky would look like the surface of a sun.

    This may all seem obvious, but it’s neat that you can figure that out with the naked eye.



  • Widely regarded as the best Seinfeld episode is The Contest. It’s about who can go the longest without masturbating, but what makes it great is that they never say that explicitly — it’s just euphemisms and insinuation. And it’s hilarious IMHO.

    I believe they initially wanted to spell it out, but the networks wouldn’t let them (I could be wrong). Definitely for the better that they danced around the topic the way they did.

    (Yes I know, Jerry Seinfeld is a problematic person, I’m just trying to answer the question…)


  • I just wish we’d have neither inflation nor deflation.

    Some tech has followed this pattern. For example: entry level Mac laptop in ~2000 was the iBook, priced at $1599 ($3k+ in today’s dollars). The current entry level Mac laptop (M4 Air) starts at $999 — cheaper in absolute dollars, and way cheaper in relative dollars.

    (Macs are just an example since Apple doesn’t have a very extensive product list, so there’s only one “entry level” laptop to choose from. And yes it’s fair to ask if the relative specs have just gotten worse, but I think this is also the opposite — the iBook was iirc criticized as being underpowered, whereas the M4 Air is afaik well regarded.)