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Cake day: July 25th, 2024

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  • I think that, in order to have this be a projection of a square, the space between the interior right angles of the space from which it was projected would have to be not just curved, but also twisted, like a Möbius strip, such that a person “walking” the square and starting from the rightmost angle leftward would start walking as if they were on your screen (their head coming out away from the screen), but then they would need to have their perspective twist so that they are now walking on the “underside” of the figure (their head now pointing into your phone). This would allow them to perceive the two “external” turns as “internal” turns, as well. Then it just needs to untwist on the way back. We just can’t see the twisting, because the lines have no width.



  • I don’t believe so. IIRC from my mineralogy & petrology courses, minable quantities of most metals occur from 4 sources:

    1. hydrothermal deposits: where water impregnates crustal rock at a high temperature and pressure, dissolving metals, which are then released as the water cools.
    2. placer deposits: where small crystals of metal ores are chipped away by erosion and carried by fluid. Those dense particles settle out from the liquid as soon as it slows down, so they all end up concentrated in specific places in rivers, lakes, etc.
    3. pegmatites & layered intrusions: these are igneous bodies which, due to the processes of their formation, tend to create either very large crystals of rare minerals (pegmatites), or significant concentrations of those rare metals over an entire magma chamber (layered intrusions). Hawaii doesn’t exhibit the necessary geologic conditions for either of these cases.
    4. banded iron formations: caused when, during the Great Oxygenation Event, microbes bound oxygen atoms to iron ions in the early ocean, effectively eating the energy of that reaction, as Iron ions became less stable with higher oxygen fugacity, and the Iron Oxide that was created, suddenly insoluble, sank to the ocean floor.

    As a very recent mantle-plume-driven volcanic arc, Hawaii doesn’t exhibit the necessary conditions for any of these in great degrees, so you would not expect to find any serious metal deposits there.






  • Absolutely, but aerobic life is more able to harness efficient energy with the use of oxygen’s INSANE reactivity, and that change was only possible because the anaerobes turned 20+% of the atmosphere into the elemental molecular form of the second-most electronegative element in the universe. Even plants, which produce oxygen gas during photosynthesis, use oxygen to power ATP synthesis. Oxygenation of the planet was absolutely requisite to allow the evolution of eukaryotic multicellular life.