this post was submitted on 18 May 2024
175 points (93.1% liked)

World News

38987 readers
2070 users here now

A community for discussing events around the World

Rules:

Similarly, if you see posts along these lines, do not engage. Report them, block them, and live a happier life than they do. We see too many slapfights that boil down to "Mom! He's bugging me!" and "I'm not touching you!" Going forward, slapfights will result in removed comments and temp bans to cool off.

We ask that the users report any comment or post that violate the rules, to use critical thinking when reading, posting or commenting. Users that post off-topic spam, advocate violence, have multiple comments or posts removed, weaponize reports or violate the code of conduct will be banned.

All posts and comments will be reviewed on a case-by-case basis. This means that some content that violates the rules may be allowed, while other content that does not violate the rules may be removed. The moderators retain the right to remove any content and ban users.


Lemmy World Partners

News [email protected]

Politics [email protected]

World Politics [email protected]


Recommendations

For Firefox users, there is media bias / propaganda / fact check plugin.

https://addons.mozilla.org/en-US/firefox/addon/media-bias-fact-check/

founded 1 year ago
MODERATORS
 

Believe it or not, no aliens were likely involved! Just some very smart humans and a massive amount of labor.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 2 points 5 months ago (3 children)

I swear that I'm not trying to be obtuse, but I have a lot of doubts.

What kind of ropes and wooden sleds, manufactured in 4000 BC, can move 80 ton stones? There are tensile limits...

[–] [email protected] 3 points 5 months ago

So, each rope only needs to be too strong for the individual worker to snap. Obviously, that's pretty easy, even with the worst natural fiber cordage - fibers are strong. Then they meet in some way, and ultimately attach to the wooden sled. The exact math for that is not straightforward, and we don't really know how they tied it off, but it's not an unusual amount of load for a large wooden structure. Assuming the sled measured 100 meters^2^ (80 tons was a special block worthy of an oversize sled), that works out to less than a ton per square meter, and a tree with 1m^2^ cross section at the trunk can weigh several tons without even considering the wind load on the foliage, which will be larger yet for most species.

80 tons is a lot, but it's not a lot a lot. Thousands of tons are pretty common if you're talking about ships, for example. Even the wooden ones; honestly wood is an underrated material.

[–] [email protected] 2 points 5 months ago

I don't know any specifics, but a bunch of ropes divides the force on each one. A bunch of ropes, plus people pushing from behind, would probably be enough force to overcome static friction without exceeding tensile limits on any one rope.

[–] VirtualOdour 1 points 5 months ago (1 children)

Yeah people really forget how recent an invention good rope is, It's not like they could just order a few hundred meters on ebay. Making all that rope would probably be more effort and expense than a lot of the stuff that people write of as too complex for them to have considered, like temporary canals or raise and drop sledding.

[–] [email protected] 2 points 5 months ago

Rope braiding is pretty fast. Especially if you're an ancient Egyptian woman who's done it full time for decades. They had hemp, which is the same stuff that rigged up the giant sailing ships of later on in history.