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388 years ago, Galileo worked out why human giants can't exist

scientificamerican.com

41–50 of 60 posts

Re: 388 years ago, Galileo worked out why human giants can't exist

#41
post #35
post #24

What about dinosaurs? not sure he's explanation makes sense given we have proven that giant dinosaurs where roaming on earth for ages.

It's answered in the article. The argument is not that giant creatures can't exist, but that they cannot exist as a simple scaled-up version of the otherwise identical smaller version.

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Re: 388 years ago, Galileo worked out why human giants can't exist

#42
> Clearly then if one wishes to maintain in a great giant the same proportion of limb as that found in an ordinary man he must either find a harder and stronger material for making the bones, or he must admit a diminution of strength in comparison with men of medium stature; for if his height be increased inordinately he will fall and be crushed under his own weight.

> While Galileo’s argument explains the nonexistence of human giants ...

The blog completely misreads what Galileo wrote. Galileo did not write that human giants did not exist, as the blog asserts. Galileo wrote how they could have existed, which could not have happened simply by scaled body structures.

Re: 388 years ago, Galileo worked out why human giants can't exist

#45

Earlier quoted context omitted.

What do you mean? The Earth does not "grow" and is not really bigger now than at any point in the past (since the creation of the Moon). On the contrary, it is losing mass through the escape of light atoms escaping, but even that is absolutely tiny. Also, the Earth is absolutely not a living organism.

The earth is both gaining mass and losing mass at the same time We are losing gases and energy (hydrogen, helium, radioactive decay) Concurrently, we are aggregating cosmic dust, micrometeorites, meteoroids, and the occasional larger body Overall a tiny loss

Right, I know that. But that’s not the point.

Re: 388 years ago, Galileo worked out why human giants can't exist

#46

Important to keep in mind that the earth was smaller back then with lower gravity. The earth grows like all other living organisms.

What do you mean? The Earth does not "grow" and is not really bigger now than at any point in the past (since the creation of the Moon). On the contrary, it is losing mass through the escape of light atoms escaping, but even that is absolutely tiny. Also, the Earth is absolutely not a living organism.

What he means is probably the idea of Earth Expansion. See Ott Christoph Hilgenberg, a disciple of Alfred Wegener, and more recently (but still a couple decades ago) Australian geologist Samuel Warren Carey. Here's a 1982 video featuring him on the topic of “Planet Earth: A Question of Expansion”:

https://youtu.be/Othb0xsvZb4 – 26 minutes

This view is kinda ostracized in geology and considered heresy.

Re: 388 years ago, Galileo worked out why human giants can't exist

#47

I’d heard this before, but it’s a fun reminder of how, in a sense, the laws of physics depend on what size you are. (Or rather, which laws have the most impact depends on the size of objects in question) Note that if you disable JavaScript you can read this without the nag wall.

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Re: 388 years ago, Galileo worked out why human giants can't exist

#48
post #21

> for if his height be increased inordinately he will fall and be crushed under his own weight > scaled-up wooden houses would not support their own roofs Hmmm this argument fails to mention giraffes, elephants or dinosaurs. (Edit: ooops it does mention elephants and dinosaurs) But clearly, land animals with bones can be quite a bit larger than humans. Similarly the houses comment ignores that large multi-story woode…

> dinosaurs True for Scientific American today, not true for Galileo. “Dinosaur” wasn’t a thing we started knowing about until the early 1800s. Benjamin Franklin died not knowing Dinosaurs were a thing. But Galileo would have certainly known about elephants though.

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Re: 388 years ago, Galileo worked out why human giants can't exist

#49
post #4

I don't know how convinced I am. First there were dinosaurs in the past, the brachiosaurus was 4 x as big as an elephant and there are probably yet undiscovered dinosaurs that were even bigger given discovery of partial fossils like the Sauroposeidon. Also we know in the past there were dargonflys with wingspans greater than 2 feet and centipedes that grew as long as a car.

They were larger but not as dense as mammals, we know had adaptations like less denser bones and different respiratory systems that allow for more efficiency and much more rapid growth into maturity. Modern birds show evidence of all these traits. When the Chicxulub extinction event happened it reset things so mammals got the upper hand on large sizes and eventully won out for the most part. Highly recommend The Rise…

« Highly recommend The Rise and Fall of Dinosaurs » (by Steve Brusatte)

This book fails to mention both Gideon Mantell (1790–1852) and Richard Owen (1804–92). It's through them that dinosaurs entered our modern, scientific world.

Re: 388 years ago, Galileo worked out why human giants can't exist

#50

Important to keep in mind that the earth was smaller back then with lower gravity. The earth grows like all other living organisms.

So does the moon though so it all evens out. Bigger gravity of earth pulls you down and bigger moon stretches you out. Hopefully no cheese eating space mold gets up there or we're done !

Yes all planets grow and are living organisms. This was common knowledge for the ancients
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