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What made Earth a giant snowball 700M years ago? Scientists have an answer

sydney.edu.au

151–160 of 193 posts

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#151

Earlier quoted context omitted.

There's a chance - however small - that WE live in that simulation.

More likely that if it's even possible, the chance is near 100%. However, it actually doesn't matter in any way whatsoever.

Except that we are living in a simulation, then it is morally wrong to be boring

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#152
post #86

Earlier quoted context omitted.

> Growing up I honestly thought that planets evolved into a sort of natural stable state that I guess I assumed would last This seems to be another expression of the truth that "people tend to mistake the limits of their view for the limits of the world."

Rumsfeld’s unknown unknowns.

Never heard of it.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#153
post #86
post #17

A recent PBS documentary did a great job talking about all the changes the earth has gone through: https://www.pbs.org/wgbh/nova/article/the-history-of-earth-i... They had a series on planets and some of their history too. Growing up I honestly thought that planets evolved into a sort of natural stable state that I guess I assumed would last until the sun or other external force decided otherwise. But it’s interestin…

> Growing up I honestly thought that planets evolved into a sort of natural stable state that I guess I assumed would last This seems to be another expression of the truth that "people tend to mistake the limits of their view for the limits of the world."

Wittgenstein reference no?

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#154
post #149

Earlier quoted context omitted.

Is it an absolutely perfect simulation? Like would we know the exact future of those hundreds of atoms in perpetuity?

I’d recommend reading up on Heisenberg’s Uncertainty Principle to understand why what you suggest is, to our knowledge, physically impossible.

Yeah, I’m aware. I was assuming some sort of aligned starting state with atoms whose configurations were perfectly known but I guess that’s not really possible.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#155
post #31

Not mentioned but still important, the Sun’s output very slowly rises over time and so was significantly lower 600 million years. We are in a ~2 billion year wide sweet spot where multicellular life can thrive in a high oxygen low CO2 atmosphere.

The Fermi paradox definitely underappreciates the Goldilocks hypothesis

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#156
post #17

A recent PBS documentary did a great job talking about all the changes the earth has gone through: https://www.pbs.org/wgbh/nova/article/the-history-of-earth-i... They had a series on planets and some of their history too. Growing up I honestly thought that planets evolved into a sort of natural stable state that I guess I assumed would last until the sun or other external force decided otherwise. But it’s interestin…

None of the videos are available for me on that page...

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#157
Coincidentally, I was just watching Myron Cook's video on the Great Unconformity (https://en.wikipedia.org/wiki/Great_Unconformity, although that page only briefly discusses the "Snowball Earth" connection).

https://www.youtube.com/watch?v=LXzDfQyUlLg

Beautiful scenery and an excellent discussion of geological strata.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#158
The more that we learn about the evolution of Earth as a planet, the more I think that the development of complex life is an exceedingly low probability event. So many things had to go “just right” for conditions on Earth to allow the formation of life.

It’s mind blowing to me that one of those things is the collision of a proto Earth that created the Moon which was just the right size to stabilize the Earth’s rotation.

On top of that, life on Earth required, vulcanism, plate tectonics, carbon cycle, magnetic field, collection of water, location and size of Jupiter and clearing of asteroids, near extinction events that were survivable by some life, etc….

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#159
post #60

Seems like a low risk approach for taking over a planet would be to just park a large shade between the planet and it's star then let it enter a deep freeze. Then you could just remove the shade and let the planet warm back up before settling down.

I wonder how that would look from a feasibility perspective... Let's see - Earth's radius is 6,378 km. Area exposed to the sun therefore would be 6,378 * 6,378 * 3.14 = 127,731,695 [1] If you wanted to block just 1% of the light, that would take a shade of 1 million square kilometers, which would be equivalent to a shade that is 1,130 km on a side. Seems like it would be tough to do given all the dust and rocks float…

To provide full Sun shade, the shield should be at L1. and it should have the same angular size from Earth as the angular size of the Sun

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#160

Earlier quoted context omitted.

There's a chance - however small - that WE live in that simulation.

The simulation theory is indistinguishable from any religious explanation.

And the Devil Will Drag You Under by Jack L. Chalker https://www.goodreads.com/book/show/584395.And_the_Devil_Wil...

https://en.wikipedia.org/wiki/And_the_Devil_Will_Drag_You_Un...

> In the year 2079, a human attempt to mine a nearby asteroid instead results in the asteroid being directed towards Earth. As catastrophic natural disasters envelop the world, Mac Walters and Jill McCulloch find themselves in Reno, Nevada. Entering a nearby bar, they encounter a demon named Asmodeus Mogart, who tells them that Earth is but one of thousands of universes set up by the mysterious Department of Probabilities, and that he can save the world if he can gather six magic jewels.

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