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A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

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Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#101

Post by vgel »

nograpes wrote: post #91

Can anyone help me understand why gears with prime numbers of teeth would not be mechanizable? For Venus the original designer faced a dilemma: the known period relation (5, 8) was very inaccurate, whereas the accurate (720, 1151) was not mechanizable because 1151 is a prime number, requiring a gear with 1151 teeth. I thought that gears with prime numbers of teeth would be advantageous because it would spread the wea…

In addition to the other comments, gears with a prime number of teeth were undesirable because they couldn't be laid out by iterative division of a circle. A gear with 64 teeth can be easily laid out by dividing the circle into fourths, dividing those fourths into fourths, and again to get 64 even divisions. For a gear with a prime number of teeth, the only option is to guess-and-check walk a pair of calipers around the circle, adjusting them iteratively until you make the exact number of steps and wind up at the exact same place. Without vision magnification, this was extremely difficult to do accurately. Clickspring (see top comment) did some experiments with a large dividing plate that makes the process somewhat easier, but it would still be far more difficult than making a non-prime number of teeth.

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#102

Post by dan-robertson »

motohagiography wrote: post #89

Forgive the naive question, but does this mean these ancient Greeks knew the world was round thousands of years ago?

The Greeks deduced that lunar eclipses were caused by the earth’s shadow and, from the consistent roundness of the shadow, that it was a globe.

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#103

Post by stryan »

DiogenesKynikos wrote: post #63
tokai wrote: post #58

Earlier quoted context omitted.

As I understand it this idea of the dark ages isn't supported by modern historians.

The "dark ages" is a good description of what happened throughout most of Western Europe after the fall of the Western Roman Empire. The nuance is that the Eastern Roman (Byzantine) Empire survived much longer, and that somewhat well organized kingdoms remained in parts of the West for a time. But there was a remarkable economic and cultural collapse in most of the former Western Roman Empire. Large cities mostly dis…

> Large cities mostly disappeared. Literacy nearly disappeared, and was only really preserved by the Church.

Neither of those were wide-spread in Western Europe during the Roman empire either. If you take a look at the major cities of the Roman Empire they're generally in either Italy, Byzantium, or North Africa[0]. All of which continued past the fall of Rome. Literacy rates were also questionable [1].

> Without large cities, roads and security, long-distance trade collapsed and the economy became much simpler.

Long-distance trade certainly did not collapse after the fall. While it did decrease to certain extent in the near time period, it rebound within a century or two [2].

[0] https://www.arcgis.com/home/webmap/viewer.html?webmap=4db977...!

[1] https://www.quora.com/Was-literacy-common-in-the-Roman-Empir...

[2] https://oxfordre.com/economics/view/10.1093/acrefore/9780190...

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#104

Post by jcrubino »

dragonelite wrote: post #92
jcrubino wrote: post #61

Earlier quoted context omitted.

The Roman were truly a successful agrarian civilization, but became lackluster in progress from there. They never made an overwhelming shift to mathematical / science based civilization. They took over Syracuse with a mandate to keep Archimedes alive, but that failed. Some scholars say the only roman contribution to math was numerals. Basically they reaped the profits of empire, and fell into the cargo cults of opule…

You mean slave labor society right, if you can't expand the empire fast enough, you "human capital" stream dries up, its like taking on too much debt and not being able to keep up with paying.

I meant The Romans, started out as an agrarian culture where Ceasars were more interested in tending the farm than politics that evolved into the spectacle that Rome is now known for.

Not ready to drop a book on HN regarding the nuance of Roman evolution just yet.

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#105

Post by kipchak »

HenryKissinger wrote: post #27
kipchak wrote: post #24

Earlier quoted context omitted.

Very broadly speaking we tend to now think of history or time as being fairly linear with progress being made while ancients tended to think of history as cyclical and those before them as random. The Antikythera mechanism or the somewhat inexplicable late bronze age collapse and the unidentifiable "sea people" that caused it are good examples to indicate there's some degree of cyclicality, wherein people stumble acr…

Peter Turchin is not a professional historian. He's a hack whose theories have been debunked.

Assuming you're referring to [1] or [2] or [3], it doesn't look like a debunking to me so much as healthy scientific debate, specifically between the Seshat and DRH projects who are both competing for limited resources-The John Templeton Foundation funds both for example.

In such a case the criticism of not being a professional historian seem odd, as the credentials of Edward Slingerland and Bret Beheim, the lead authors of the critical papers, seem to be fairly comparable to Turchin's.

[1]https://psyarxiv.com/jwa2n/

[2]https://eslingerland.sites.olt.ubc.ca/files/2019/09/Historia...

[3]http://peterturchin.com/cliodynamica/what-came-first-big-god...

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#106

Post by [deleted] »

lurquer wrote: post #73
stryan wrote: post #69

Earlier quoted context omitted.

> Well, almost all of the work of Greek philosophers and their science and philosophy achievements were in Catholic Europe completely forgotten and actively censored for centuries. While less available they were still known and studied and certainly not censored. Neo-Platonist and Aristotelian thought was very influential in the Post-Antiquity and Early-Medieval time periods: see the Desert Fathers and the Scholastic…

You’re not arguing against a competing view of history. You are arguing against an ideology. Save your breath. This is their view of history: Ancient Rome was enlightened. Then Christianity destroyed all the worlds great accomplishments. Then, Galileo showed everyone who was boss. Oh yeah... a corollary to this version: Islam was as nearly enlightened as Rome and would have ushered in an age of elegant sophistication…

[deleted]

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#107

Post by NoImmatureAdHom »

dragonelite wrote: post #92
jcrubino wrote: post #61

Earlier quoted context omitted.

The Roman were truly a successful agrarian civilization, but became lackluster in progress from there. They never made an overwhelming shift to mathematical / science based civilization. They took over Syracuse with a mandate to keep Archimedes alive, but that failed. Some scholars say the only roman contribution to math was numerals. Basically they reaped the profits of empire, and fell into the cargo cults of opule…

You mean slave labor society right, if you can't expand the empire fast enough, you "human capital" stream dries up, its like taking on too much debt and not being able to keep up with paying.

Everybody slaved. The Romans were just better at it (and most other things).

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#108

Post by deek »

jcrubino wrote: post #61
sho_hn wrote: post #45

Earlier quoted context omitted.

In the case of the Antikythera mechanism, it turns out the knowledge and technology weren't entirely lost. There's a fairly well-established throughline now from Babylonian observation-based astronomical tables to Greek philosophical views and mathematics (and craftmanship) to Arabic astrolabes (retaining some of the gear-train tech) and then back to Europe, to the monastic astronomical clocks. Then the escapement wa…

The Roman were truly a successful agrarian civilization, but became lackluster in progress from there. They never made an overwhelming shift to mathematical / science based civilization. They took over Syracuse with a mandate to keep Archimedes alive, but that failed. Some scholars say the only roman contribution to math was numerals. Basically they reaped the profits of empire, and fell into the cargo cults of opule…

They dabbled in engineering as well

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#109

Post by NoImmatureAdHom »

shakezula wrote: post #49
phkahler wrote: post #36

Earlier quoted context omitted.

That's why odd gaps appear. Like an article about how China can't manufacture the balls for ball-point pens, or critical parts for jet engines. Maybe a few missing pieces are why Intel cant seem to figure out EUV lithography. None of these things are trivial and probably not documented in a way where a noob could pick them up.

Even just the specific knowledge of building a house is probably a generation removed from most people these days. It scares me to think of just how fragile we really are.

https://xkcd.com/1513/

Re: A Model of the Cosmos in the Ancient Greek Antikythera Mechanism

#110

Post by NoImmatureAdHom »

HenryKissinger wrote: post #27
kipchak wrote: post #24

Earlier quoted context omitted.

Very broadly speaking we tend to now think of history or time as being fairly linear with progress being made while ancients tended to think of history as cyclical and those before them as random. The Antikythera mechanism or the somewhat inexplicable late bronze age collapse and the unidentifiable "sea people" that caused it are good examples to indicate there's some degree of cyclicality, wherein people stumble acr…

Peter Turchin is not a professional historian. He's a hack whose theories have been debunked.

You're right, he's not a professional historian. And that's a good thing, because History the academic field is hopelessly sick and outdated.

Turchin may not be right about everything (or most things), but the kind of thing he's trying to do is the path forward. The really interesting action in history (broadly construed) is all being done by people doing history within analytic paradigms, like Turchin. Look for work by people who call themselves economic historians.

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