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Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

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Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#191
post #138

Earlier quoted context omitted.

Th narrative of "the west doesn't manufacture anything" is greatly oversold. The US makes more steel than it did 40 years ago, for example. Sure, we make fewer hairs and t-shirts, but it's natural for that stuff to chase lower labor costs. We're also an agricultural powerhouse. Now, for sure we have fallen a bit behind in making chips, but that may change.

So we are the Romans. We can make swords and bread! We'll do great in WWIII!

Because we hit max depth, I'll respond to your bizarre fever dream about the Millennium Challenge and some hypothetical war with China. The only things that matters in a war between nuclear states is that both sides view it as too terrible to entertain. Nuclear subs mean that the US always has the option to deal a killing blow even if everything else fails. And if it comes to that, nothing else matters anyway, so why worry about it?

They can go on fancifully pretending to plan for 500 years from now, and we'll continue to innovate, live well by comparison, and at the end of the day there's relatively little reason for us to have a major conflict.

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#192
post #124

Earlier quoted context omitted.

Humans left a ridiculous amount of stone tools which last basically indefinitely in the fossil record (and unlike bone fossils, don't require super special conditions to preserve them). So I think we'd have enough evidence from modern artifacts made of similar types of materials. A car buried under sediment would rust all out, but you'd be left with a big car-shaped bunch of rust as well as chunks of pure metal which…

Maybe the archaeologists of the future would weave scholarly narratives as to how these ferrous-based lifeforms lived, what their diet was and how they came to perish. Film-makers would use stop-motion techniques to depict battles between Fordusprefectops and Chevroletcamaro-Rex whilst their own early ancestors look on, clad in loincloths and bras made from footwell mats.

Like in David Macaulay's "Motel Of The Mysteries".

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#193
The thing that really gets me is just how densely the whole mechanism is packed together. What a masterpiece. The techniques must have been developed incrementally over many revisions of the machine, perhaps over several lifetimes by various machinists and/or designers.

Sadly I read somewhere that the "slop" between the gears (the mechanical imperfections that add or multiply together over many gears) would overwhelm the more complex calculations that some of the machine was intended to perform.

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#194
The presumption that other people aren't smart enough to do what you can or imagine has a name: bigotry. The "shouldn't exist" is bigotry.

It's also evidence that we see even today that knowledge is fragile and easily lost when it has a large tacit component. Most things technological are highly fragile because half of the knowledge required to create them is tacit.

See also: "FOG BANK".

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#195

The presumption that other people aren't smart enough to do what you can or imagine has a name: bigotry. The "shouldn't exist" is bigotry. It's also evidence that we see even today that knowledge is fragile and easily lost when it has a large tacit component. Most things technological are highly fragile because half of the knowledge required to create them is tacit. See also: "FOG BANK".

Presumably you're talking about the classified nuclear material: https://en.wikipedia.org/wiki/Fogbank

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#196
post #72

Previously on HN: https://hn.algolia.com/?q=Antikythera+mechanism I am curious, is this device as fascinating to the average person as it is to the average HN'er? I suspect not, but I don't really understand why. I myself have read quite a few articles/posts and watched a few videos about it. Every time I re-encounter it, I get sucked back in. See also: https://en.wikipedia.org/wiki/Baghdad_Battery https://en.wikiped…

It seemed like a near-mystical piece of technology when I encountered it as a kid watching The History Channel. Tech-minded people probably self-select here anyway...

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#197

I realize how much I miss the #dislikes for videos like these. The title sounds clickbaity and #dislikes would confirm that. I guess it is not clickbait given that it's on hackernews and by the BBC, but if this context was missing...

Would YT remove comments which posted the dislike count from Archive.org?

Automate it!

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#198
post #63

Earlier quoted context omitted.

Coal, yes. Iron, wouldn't the iron we moved to the surface be even more accessible? We didn't destroy it, just rearranged and concentrated it?

Stone coal could be, at least partially, substituted by charcoal - and often was in the past, where reachable underground coal reserves were not available.

"So by weight charcoal and anthracite coal have an energy density of about 30 MJ/kg, while poorer kinds of coal range down to half of that." (https://www.reddit.com/r/askscience/comments/udjl5/charcoal_...) However, the density of charcoal is much less than that of coal: 200 kg/m^3 vs 1500 kg/m^3 (for solid anthracite).

Producing 1kg of charcoal requires 3-4kg of wood. (Producing the 900°C for the process is an exercise for the reader.) (https://www.fao.org/3/y4450e/y4450e11.htm)

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#199
post #179

Earlier quoted context omitted.

The problem will be a lack concentrated deposits making post-collapse (and new) industrial efforts much harder. A pile of rust from one tractor in someone's back yard is not going to be worth the effort to mine and refine. Possibly an analogous situation is the history of steel in Japan and their efforts to extract iron from sand, since they don't have significant iron ore to mine on their island.

The pile of rust that use to be a tractor, sure, that's not worth much. The pile of rust that use to be a city though... surely that's more concentrated than the rust mixed with rock (or clay) that we originally extracted it from?

Most likely not: https://en.wikipedia.org/wiki/Iron_ore, it's almost 50% iron in the worst case and can be up past 70% in the best case. The geological processes that form this ore in the mantle do a pretty good job of concentrating iron by density but it takes geological scales of time to do so and have it lifted back up through the crust. We might have to excavate a lot of earth to get to the concentrated vein of ore but when we find it it's relatively easy to chase and turn into usable iron once you know a little bit about mining and smelting as a society.

A city decayed to rust is going to be a thin layer of iron spread out over miles with some hot spots like where a building once stood (but presumably without a map of the city in this distant future scenario), but there won't be a vein of concentrated ore. Distributed rust can definitely be turned back into pure iron but the energy requirements are going to be substantially higher to do so since you're going to have to sift through much more material to collect it, more material to separate and concentrate it, more material to smelt off, and your operations will have to be more mobile to retrieve it over a larger area. That's why I think retrieving iron from our society will be more like extracting iron from ironsands (2-20% iron), and it will have similar effects on that subsequent society that sits between us now and some future point where geology has re-supplied it to the surface millions of years from now.

Re: Antikythera Mechanism: An ancient 'computer' that 'shouldn't exist' [video]

#200
post #11

Jonathan Blow's talk 'Preventing the Collapse of Civilization' goes into detail about how technology can regress, with the Mechanism being one example. This kind of thing is far more common than we think, most would be surprised to learn that Ancient Greece had writing for about 600 years before forgetting it. There was no writing in Greece for over 400 years, until they adopted the Phoenician alphabet around 730 BC.…

I'd add to his argument, that the problem with software and uptime is that every time we add a layer of abstraction or library, the five 9s factor may apply.

    Math.pow(.99999, 1) - One dependency.
    Math.pow(.99999, 2) - Two dependencies.
    ...
    Math.pow(.99999, N) - N dependencies.
And that assumes everyone is aiming for 99.999% uptime. Which isn't true.

There's other factors, but that's the one I'd point out.

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