51–60 of 181 posts
A highly responsible civilization that achieves space fairing tech could rebuild its environment, leaving a clean planet as a gift for future species to emerge, and move to the stars. Sort of artifical-creationism, but phycally achievable, it's a matter of civilization goals.
Why would they spend resources doing this?
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This argument disproves fossils. E: To be pedantic, it only disproves most fossils.
And, as predicted by the argument, the fossils don't abound, and to find them you have to start digging.
Maybe the biggest obstacle to archeology is having people around who are interested in explaining what they're seeing. Science is a very rare thing for human cultures to spontaneously do. Even the 1000s of years old Chinese civilization never invented science and had to wait for it to be imported. I tend to think that human societies naturally actively discourage science because they'd quickly think up and memetically spread myths for any unexplained phenomena then anyone challenging the popular myths would have to be a misfit and that would come with punishment because misfits were generally harmful to society in the short term.
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Has anyone methodically looked for artificial materials like microplastics in the geological strata?
Yes, in that people try and identify what’s there. No, in that it’s not expected to find evidence of a prior advanced civilization. The prior existence of oil as an easily recoverable resource is a strong indicator that nothing like our civilization existed in the last several million years.
If they discovered better sources of energy a little faster, they would stop pumping almost immediately. But for politics, the US might easily have started the switch to wind power forty years ago, and billions of barrels' worth would still be in the ground.
Every time this pops up on HN, people post insisting that it won't all go away, that the skyscrapers will, somehow, still be there. No, they won't. Look at any place in the world where there are mesas. All of the land around the mesa used to be level with the top of the mesa. It has all eroded away, and in only a few million years. So, the metals will corrode, collapse, and wash away. The stone will erode away. The c…
I strongly agree with this take. I've been working on a paper comparing the effects of the Anthropocene to mega catastrophes in the geologically recent past. In addition to the Younger Dryas Impact (12kya), there's the Oruani (26kya) and Mt Toba (77kya) eruptions. From my calculations, it seems the climate change from each of these dwarfs any actions humans are currently capable of, namely petrocarbon burning and als…
The US is supposed to switch from HFCs to something else around 2024. A lot of companies are switching to propane refrigerant ahead of time because it's cheaper, and worry about it igniting has dissipated, vs. looming ecological catastrophe.
BTW, to my knowledge the Greenland structure has not been reliably dated, nor even confirmed to be a bolide crater (although it seems like one). YD bolide impact seems pretty secure, though.
Temperature change might be a relatively minor effect of the CO2 concentration peak. Ocean acidification causing a collapse at the base of the food web, as marine animals become unable to fix calcium to make shells, might be more important.
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And, as predicted by the argument, the fossils don't abound, and to find them you have to start digging.
I wonder if that's always been the case. Maybe humans quickly cleaned up all the easily accessible fossils before realizing what they were. Ancient Greeks thought they'd found a giant's bone and other cultures seem to have used dinosaur fossils as inspiration for myths of dragons. Even western researchers a few hundred years ago thought dinosaur bones were just recent animal bones. Imagine how careless every previous…
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Yes, in that people try and identify what’s there. No, in that it’s not expected to find evidence of a prior advanced civilization. The prior existence of oil as an easily recoverable resource is a strong indicator that nothing like our civilization existed in the last several million years.
But not finding fossil fuels wouldn't tell you anything, because nobody knows how much there ought to be. If they discovered better sources of energy a little faster, they would stop pumping almost immediately. But for politics, the US might easily have started the switch to wind power forty years ago, and billions of barrels' worth would still be in the ground.
So some other civilization could exist without using it, but they would look nothing like ours.
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The oldest known iron artifacts, ca 3200BCE: https://ars.els-cdn.com/content/image/1-s2.0-S03054403130020... https://www.sciencedirect.com/science/article/pii/S030544031...
I wonder how it is that the iron in meteorites doesn't just dissolve away. Any thoughts on that?
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So a civilization thousands years more advanced than us failed to go to space (evidenced by the fact that they did not leave behind any space junk) but somehow produced energy from crystals?
> evidenced by the fact that they did not leave behind any space junk Whatever space junk we leave behind will be gone 100 years from now. https://www.nasa.gov/news/debris_faq.html
Geosynchronous satellites 35,786 km (22,236 mi) are going to be up there for a very long time.
PS: If you’re interested https://aiaa.kavi.com/apps/group_public/download.php/3172/IS...'
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So a civilization thousands years more advanced than us failed to go to space (evidenced by the fact that they did not leave behind any space junk) but somehow produced energy from crystals?
FWIW, space junk wouldn't necessarily survive that long. Things on lower orbits would deorbit themselves quickly without station keeping. Things on higher orbit would get pushed away by solar radiation over long time, and degrade under high-energy radiation (such as UV rays). What remains would be hard to find, because space is big , so it would have to be fairly large and/or fairly reflective for us to notice now.