Mohamed

Decentralise everything!

  • 2 Posts
  • 141 Comments
Joined 5 years ago
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Cake day: June 27th, 2021

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  • I think it is possible, logically at least, to have gods, free will and souls even if everything were physical matter, unless you define those terms specifically to be metaphysical but then its like a True Scotsman fallacy.

    Physicalism might be the most viable, but that does not mean its viable enough. There are huge holes - we have no explanation for consciousness, sentience, free will, physics still doesn’t explain everything physical, and quantum mechanics is such a weird aberration of physical matter I am tempted to not call it that.

    However, nothing beats the scientific method for truth finding at the moment. And, at the moment, the scientific method is content with only giving us physical results.












  • I think it is more specifically electric planes as large as commercial airline passenger planes are impossible. It has a lot to do with battery mass to energy content ratio. Kerosine is about 46.4 MJ (megajoules) per kilogram. Lithium-air batteries, for example, only have about 6.12 MJ/kg.

    So, that means you need 7 times as much battery (in mass) to have the same energy content of kerosine fuel. Naively, we can maybe say that means electric planes only have 1/6 of the range of an equivalent kerosine plane.[^]

    Interestingly, lithium-air batteries theoretically have the largest possible energy density for any battery at 40.1 MJ/kg.

    ^ The calculations are really basic and probably only slightly reflect reality (since there are many other important factors. For example, Hydrogen has a lot more energy per kilogram than kerosine, but because it is much less dense, it has much less energy per m^3 than kerosine. This has made hydrogen gas very impractical for either internal-combustion engines, or planes), but I think it gives an idea of what the problem is.


  • Passive or Active Ventilation. The idea is to encourage air to pass through the home, which helps with removing heat from inside. Passive Ventilation would be opening windows, using wind catchers, etc. This depends on the design of your home, among other things that you probably don’t really have control over. Active ventilation is the same idea, but you use strategically placed fans to induce good airflow. For example, if you have two windows that are opposite to each other, you can place a fan at one window to intake air, and a fan at the other window as exhaust.