Gravitational wave researchers cast new light on Antikythera mechanism mystery

The paper [here](https://bhi.co.uk/wp-content/uploads/2024/06/07-HJJuly24-AOT...) makes it clear that these researchers (whose main topic is gravitational waves) have used Bayesian analyses to estimate how likely different counts for holes present in the full calendar ring are. This is cool, but the bit about "techniques developed to analyse the ripples in spacetime" is, well, making reference to Bayesian analysis.

This is cool (lots of necessary context) but the paper itself is downright gorgeous

https://bhi.co.uk/wp-content/uploads/2024/06/07-HJJuly24-AOT...

Oh and quick timesaver for all the dubious people like me: they applied general statistical techniques from their gravity work to parsing the fragments of the computer we have. There’s no direct connection between the two subjects, otherwise.

EDIT: some kinda humorous scientific meta-commentary at the very bottom of the paper: they were able to get the anthropology paper based on these findings peer reviewed and published in print well before this technical paper finished peer review. If I were an Academia pen tester, this is the kind of race condition that I’d look for!

This is a cool statistical paper, one of many depressing papers that makes me wish I knew more math. The "gravitational wave" angle is apparently that it uses some statistical methods that originated in gravity wave research. There are no ultra-sensitive new measurements or anything like that. They use the same X-ray measurements as the Clickspring article from a few years ago (https://bhi.co.uk/antikytheramechanism/) and basically support Clickspring's conclusion (that the Antikythera was a lunar calendar) with increased statistical confidence.

I'm currently building this 3d printed version of the Antikythera mechanism. It's not easy:

https://www.printables.com/model/284372-antikythera-mechanis...

It is insane how complicated this is, and this is a simplified version of the actual thing. This schematic of the proposed full mechanism (I think it's hypothesizing some of the missing parts) blows my mind: https://upload.wikimedia.org/wikipedia/commons/5/59/Antikyth...

If you have a 3d printer, I really am enjoying the project and recommend it.

Greeks were cooking with gas (from the paper): “However, we note that the degree of manufacturing precision is remarkable, with standard errors in hole positions of only 0.028mm radially, and 0.129mm azimuthally. Budiselic et al. quote a standard deviation for their individual position measurements of 0.037 mm, so a good deal of the radial error may come from the measurements of the X-ray images themselves.”

> Professor Woan used a technique called Bayesian analysis, which uses probability to quantify uncertainty based on incomplete data, to calculate the likely number of holes in the mechanism using the positions of the surviving holes and the placement of the ring’s surviving six fragments. His results showed strong evidence that the mechanism’s calendar ring contained either 354 or 355 holes.

> At the same time, one of Professor Woan’s colleagues at the University’s Institute for Gravitational Research, Dr Joseph Bayley, had also heard about the problem. He adapted techniques used by their research group to analyse the signals picked up by the LIGO gravitational wave detectors, which measure the tiny ripples in spacetime, caused by massive astronomical events like the collision of black holes, as they pass through the Earth, to scrutinise the calendar ring.

The title was very clickbait

The paper notes a (to me) amazing thing. The object of the researchers' Bayesian analysis is the number of holes likely to have been made in a metal ring, of which only a fragment remains. They think either 354 or 355 holes, on a 77.1mm radius.

The amazing thing is that the holes were placed with an average radial variation of only 28µm. This is about 0.001 inches. 2000 years ago. Our ancestors had some serious skills.

> Gravitational wave researchers cast new light on…

Seems like they are a bit out of their lane, as light is an electromagnetic phenomenon, a completely different force from gravitation.

More seriously: the fact that the two scientists happen to have been doing data analysis on gravitational data isn’t really relevant to the work, rather it was pulled out to make us click on the article title.

Super interesting work though, and not what I would have expected!

I would love a website with a 3D breakdown of the Antikythera mechanism that let one peruse it in space, (dis)assemble it, and see how it functions (at least, to be best of our understanding.) Are we far enough along in what we know of it to have such a resource?

Is there evidence that it was actually made in Greece or could it simply have ended up there?