6 HN users recommended this explainer5 months2021–2025score 5.5
Years with an HN recommendation, 2007–2026
Recommended in threads on analog computing, photonic chips, AI hardware and tide prediction as an engaging history of Kelvin's machines.
Veritasium traces analog computers from the Antikythera mechanism and Kelvin's tide-predicting machines to fire control and modern analog approaches. It explains how these machines computed continuously rather than digitally.
“His video before this one[1] goes into detail on that, and it was incredible.” (HN, 2022)
In the intro to this video he mentions analogue computers predicting tides. His video before this one[1] goes into detail on that, and it was incredible. In the 1800s, Lord Kelvin spent years working on tidal rise and fall patterns, applying Fourier Transforms to break them down into ten individual sine waves, then combining those sine waves back together to predict future tides. And built analog computers to do all the involved integration, multiplying and summing. It's a part of the history of computing I'd never heard of, despite hearing quite a lot about the dawn of electro-mechanical computers in the early 1900s. [1] [this video]
Details Kelvin's tide-predicting analog computers; incredible history.
You might be interested in the analog computers that were used to compute tide tables back in the day. It's quite fascinating how they even managed to do basic Fourier transforms without electricity: [this video]
Tide-computing analog machines doing Fourier transforms without electricity.
basicly, we can do things like matrix operations and differntial equations using specialized hardware that performs computation over analog signals rather than buidlign discrete systems. the end result is that we dont' need anywhere near the level of compute to do the job as its done using an analog of the physical process. here's two youtube videos that explain is much better than I could. [this video] [link] suffice to say, your average house fly exhibits behavior that absolutely dominates our best drones and with a fraction of the circuitry.
Explains analog computing hardware better than commenter could.
It's a big area of research in AI. Veritasium has two great videos on it: [link] [this video] I found a hackernews discussion for the second one: [link]
The author mentions they were inspired by the Veritasium video on the same topic (without the Lego). [1] I thought I'd link the previous HN discussion. [2] [1] [this video] [2] [link]
The product presented: [link] made by [link] The company presented: [link] This is the second video (of a series of two) by Veritasium about analog computers. The first one was [this video] and discussed on Hacker News at [link]
First of two Veritasium videos on analog computers.
That's really neat. Veritasium did a couple of videos on analog computing a year ago. I'm glad there are people lowering the barrier to entry. [this video] [link]
Veritasium's analog computing videos from a year earlier.
Adding to this list of unorthodox approaches, by modern standards: I've heard in some French conferences of Etienne Klein (I'm not sure how romanticized this is though) that Einstein had some breakthrough while being in a half-asleep state. Here's another similar instance[0][1], better documented, of an engineer working on an automatic level recorder, and "realizing" in a dream that it could be used to improve the accuracy of anti-aircraft guns (WWII). [0]: [link] [1]: [this video]
Cited for engineer's dream about anti-aircraft gun accuracy.
I used to know nothing about Lord Kelvin except he said things like " It seems, therefore, on the whole most probable that the sun has not illuminated the earth for 100,000,000 years, and almost certain that he has not done so for 500,000,000 years "[1] and allegedly "everything which can be discovered, has been discovered"; until last year's Veritasium video on YouTube[2] about analog computers, and learned he invented tide-predicting analog computers to "substitute brass for brains" and add sinusoidal curves, and a mechanical integrator to separate out individual sinusoidal frequencies from the sum. [1] [link] [2] [this video] from about 3 minutes.
Learned Kelvin invented tide-predicting analog computers.
The Thomson (also known as Lord Kelvin of degrees K fame) tide predicting machine takes us back to the late 1800s. [link] One implementation of it was a notable part of WWII: > They came to be regarded as of military strategic importance during World War I, and again during the Second World War, when the US No.2 Tide Predicting Machine, described below, was classified, along with the data that it produced, and used to predict tides for the D-Day Normandy landings and all the island landings in the Pacific War. [link] From Veritasium : The Most Powerful Computers You've Never Heard Of - the tide calculator plays a prominent part of the video. [this video] (the next video is also in the same topic - Future Computers Will Be Radically Different [link] and that gets into more modern implementations and uses - [link] is the device shown in the video).
Tide calculator plays a prominent part of the video.
So... I remember math including doing quite a bit of geometry by hand and with real tools, at least initially. "Math" is not just the symbol stuff written with a pencil, or with a keyboard. The mechanical analog computers of old (e.g. [this video] , or [link] ) are examples too that math is more than symbol manipulation.
Example that math is more than symbol manipulation.
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
Plays via YouTube's privacy-enhanced embed
14 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.
Read more
Citations, criticism and jokes
Read more
Read more