Links for 2022-01-17
“Spaced repetition gives you exponential returns for a linear increase in effort. It's hard to overstate exactly how powerful this is. One of the very, very few things in life that isn't subject to diminishing returns.” — @kanjun https://numinous.productions/ttft/
Study reveals no evidence of life on Mars meteor found in Antarctica https://thehill.com/homenews/589728-study-reveals-no-evidence-of-life-on-mars-meteor-found-in-antarctica [how this is good news: https://www.nickbostrom.com/extraterrestrial.pdf / see also: recent findings that made the Fermi paradox more puzzling (and scary) https://axisofordinary.substack.com/p/recent-findings-that-made-the-fermi]
Why is the Nuclear Industry Stagnant? A deep dive into the engineering and economic realities of building and operating nuclear plants safely. https://austinvernon.site/blog/nuclear.html
"Our results demonstrate that the more similar two persons are in autistic traits, the higher is the perceived quality of their friendship" https://pubmed.ncbi.nlm.nih.gov/33104781/
Behind closed doors at the UN’s attempted “takeover of the Internet” https://arstechnica.com/tech-policy/2012/12/behind-closed-doors-at-the-uns-attempted-takeover-of-the-internet/
New GWAS on height is the biggest genetics study to date with 5.4 million individuals. The top ~12k genetic variants explain ~40% of individual differences in Europeans, and 10-20% in other ancestries. https://biorxiv.org/content/10.1101/2022.01.07.475305v1
Long-term two-photon imaging of spinal cord in freely behaving mice
https://biorxiv.org/content/10.1101/2022.01.09.475306v1?rss=1
Sex differences in chess participation are larger, rather than smaller, in more gender-equal nations (N = 803,485; 160 nations) https://journals.sagepub.com/doi/abs/10.1177/09567976211034806
Journey to the centre of the Earth: An introduction to The KMT Project: “This cutting-edge endeavour will enable volcanologists and geothermal scientists to directly sample and observe the previously uncharted volcanic world that lies beneath our feet.” https://www.volcanodiscovery.com/view_news/169863/Journey-to-the-centre-of-the-Earth-An-introduction-to-The-KMT-Project.html
"Nothing like this will be built again" — Charles Stross tours a nuclear reactor complex. https://www.antipope.org/charlie/blog-static/rants/nothing-like-this-will-be-buil.html
The world's shortest explanation of Gödel's theorem
by Raymond Smullyan, from his book '5000 BC and Other Philosophical Fantasies'
We have some sort of machine that prints out statements in some sort of language. It needn't be a statement-printing machine exactly; it could be some sort of technique for taking statements and deciding if they are true. But let's think of it as a machine that prints out statements.
In particular, some of the statements that the machine might (or might not) print look like these:
P*x (which means that the machine will print x)
NP*x (which means that the machine will never print x)
PR*x (which means that the machine will print xx)
NPR*x (which means that the machine will never print xx)
For example, NPR*FOO means that the machine will never print FOOFOO. NP*FOOFOO means the same thing. So far, so good.
Now, let's consider the statement NPR*NPR*. This statement asserts that the machine will never print NPR*NPR*.
Either the machine prints NPR*NPR*, or it never prints NPR*NPR*.
If the machine prints NPR*NPR*, it has printed a false statement. But if the machine never prints NPR*NPR*, then NPR*NPR* is a true statement that the machine never prints.
So either the machine sometimes prints false statements, or there are true statements that it never prints.
So any machine that prints only true statements must fail to print some true statements.
Or conversely, any machine that prints every possible true statement must print some false statements too.