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How many people did it take to build the Great Pyramid?

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Re: How many people did it take to build the Great Pyramid?

#51

Post by goto11 »

mehrdadn wrote: post #3
burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

> I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. That's mind-boggling. Why would building a cathedral/mosque/temple take longer than a lifetime (or half)?

Some cathedrals took centuries to complete, but mostly because of long gaps in active work due to lack of funds or interest.

Furthermore cathedrals were often build iteratively - e.g. someone finances a new tower to add to an existing centuries old building.

Re: How many people did it take to build the Great Pyramid?

#52

Post by weinzierl »

toomanybeersies wrote: post #41
est31 wrote: post #9

Earlier quoted context omitted.

There is a star trek episode where they encounter a civilization which has built a benevolent AI a long time ago and has since lost capabilities to do much more than give commands to the AI. Our society has managed to write down some things like math for example so our knowledge as species won't be lost if mathematicians suddenly died. But it's harder to find permanent storage for the more skills based human activiti…

I don't know if NASA themselves could stick Saturn engines onto new rockets, but I reckon the Air Force probably could. Air force technicians are pretty good at fabricating and fitting parts from what I've seen. Skills like hand fabrication and fitting aren't something that you can store. You can record videos or interview skilled tradesmen as much as you want, but the real skill is something that is learned through…

I worked in aerospace during the transition from Ariane 4 to Ariane 5. The Ariane 4 was a versatile modular launch system and widely considered a successful project. The Ariane 5, on the other hand, was struggling at the time. A large part was because it originally was designed to be a launcher for the Hermes space plane. Hermes was never built, but the design decisions that were made because of it had many negative consequences for the Ariane 5. Most importantly it was not very economic for launching smaller satellites.

It was quite natural to think of enhancing the successful Ariane 4 design instead of building Ariane 5. From the conversations I remember from that time this was not considered a viable path - mostly because the supply chain of the Ariane 4 parts had already gone dry and it was not considered realistic to rebuild them.

For me as a young engineer this was very surprising, but a few years later I understood two things much better:

1. The knowledge to build projects of this scale is very distributed. There were subcontractors over subcontractors (spread over several countries) and every one had some tacit knowledge viable for the project.

2. Setup cost for parts production is relevant, even for the small series productions common in aerospace.

Re: How many people did it take to build the Great Pyramid?

#53

Post by noneeeed »

jiggawatts wrote: post #49
utopcell wrote: post #48

Ahem.. I'm just going to drop this link here on how the pyramids were _really_ built: https://youtu.be/TJcp13hAO3U

That's rather... imaginative. Certainly, water played a role: much of the stone was shipped from quarries some distance away. It's also imaginable that they used canals to bring the blocks further inland, closer to the pyramid construction site. However, the near-vertical water tower and lock system would be a challenge to build today, let alone with the technology of the era. The pyramids were built before the wides…

That was really interesting. Itr's weird to think of how many mundane technologies actually had to be invented, and how things would have worked before. The idea of a boat built without nails is kind of crazy.

Re: How many people did it take to build the Great Pyramid?

#55

Post by Aeolun »

pvg wrote: post #45
burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. I wonder whether that's not really more the exception rather than the rule - some famous cathedrals just took a long time. But lots of huge projects were completed in one or two decades or less - the pyramids, the Co…

Kind of makes sense, since the person that commissions these things generally wants to see them completed in their lifetime.

Re: How many people did it take to build the Great Pyramid?

#56

Post by Aeolun »

peeters wrote: post #44
umvi wrote: post #40

Earlier quoted context omitted.

Yeah they just calculate the potential energy as if workers can move limestone blocks with perfect efficiency in frictionless conditions. It wouldn't surprise me if it took 2-4x its potential energy (or more) to move any given block into place.

How many people does it take to push a two-ton rock up a hill and then back to where it started? Apparently zero.

If you're not careful, the rock will go back by itself.

Re: How many people did it take to build the Great Pyramid?

#57

Post by SideburnsOfDoom »

octabond wrote: post #27

You are assuming optimal efficiency for each human. Don't think that was the case

Right. Energy analysis is cool, but it places a lower bound on the amount of work needed, that's all.

If you're only counting energy needed to raise stones, then you're costing at zero a piece of stone, cut and transported to ground level near the pyramid. But that is hard work.

Re: How many people did it take to build the Great Pyramid?

#58

Post by onion-soup »

Now divide total number of blocks by 30 years and you get 1 multi ton block being laid every 9 minutes.

The current theories are joke, this numbers don’t add up. Don’t be afraid to challenge the “academic” theories, as you see, there is no math behind them.

Re: How many people did it take to build the Great Pyramid?

#59

Post by goto11 »

mehrdadn wrote: post #6
obastani wrote: post #5

Earlier quoted context omitted.

Not an answer to your question, but the Sagrada Famila [1] began construction in 1882, and is projected to be completed around 2030. It's an immense (and beautiful) structure. Just want to point out that it's not just a matter of the buildings being built a long time ago; this kind of long-term construction is still happening today.

I... just can't wrap my head around this. Is it that they actually take that long with enough people, or they have too few people working on them?

Funding has been the limiting factor, as far as I know. There have been long breaks where no work was being done, and it was damaged during the civil war. Also the building is immense and very detailed.

Re: How many people did it take to build the Great Pyramid?

#60

Post by ncmncm »

If they built the Great Pyramid in the advertised 20 years, that means placing a 2.5-ton block every 4th minute, 24 hours a day, 365 days a year. If they stopped at sundown, it's every 2 minutes. If they broke half the year to farm, that's one each minute. But let's guess they had enough surplus to work year-round; so, 2 minutes.

Suppose they took 600 years, instead; then it's one per hour.

Which is harder to imagine, cutting, moving, lifting and placing 30 blocks in every waking hour for 20 years, or placing one per waking hour, non-stop, for 600 years? Each seems less possible than the other.

I don't know of any firm evidence for when any of the pyramids were built. We can guess that the bent and red pyramids were built first, but they could just as easily be poor copies attempted a thousand years later, or ten.

There is a fluorescence technique to discover when a cut limestone face that has been covered for centuries was last exposed to sunlight, but I don't know of it being used on any Great Pyramid block. One would not expect Egyptologists to advocate for such a test, because only two outcomes are possible: they were far enough off to be embarrassed; or not, and it was useless. (Either way, better not.)

They built these things with perfectly straight, slanting tunnels a few inches wide running from inner chambers almost to the surface, for no known reason. Some people say they point at certain mythologically important stars on equinoctal days, but I have not been able to get confirmation of that.

One thing well established is that none of them were tombs. When somebody finally battered their way into each, maybe 4300+ years later, all the chambers were empty and unmarked. (Except one has an empty stone box in it big enough to be a coffin or bathtub.)

There are lots of examples of 20-, 30-, 60-ton basalt boxes cut from living rock with perfect right-angled inside corners, and moved through funerary complex tunnels barely big enough. Take off the (10-ton) lid and they're empty. It's anybody's guess what they were for.

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