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Joined 1 year ago
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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.










  • Left pedal looks more like a dead pedal to me.

    And as others have said, change in direction is still acceleration. That’s part of Newton’s (apocryphal?) apple story — he witnessed an apple falling, and wondered why the moon doesn’t also fall. His amazing insight is that it does fall (accelerate), it’s just that it falls in such a way that it orbits, rather than hits, the Earth (for timescales relevant to a human).




  • I grew up with a hand-cranked popcorn maker. Then, in grad school, I realized that you don’t actually need any of that, just a pot with oil.

    I heat up (medium) a tiny bit of neutral oil with a few kernels until they pop. Then I add ~1/4C neutral oil and ~1/3C popcorn kernels. When I can count to ten between pops I turn it off, empty in bowl, drizzle with olive oil and add salt and nutritional yeast (and MSG if you have it).