• Random,  Science

    Test

    Test The Usual Colors of the Sky Why is the sky blue? Why are sunsets red? The answers and explanations to these questions can be found fairly easily on the internet. But there are many subtle “Wait a minute…”-type questions in between the cracks that seem to necessitate subtle answers and more “difficult” searching around the internet to find those answers. So, why is the sky blue? No, but first, what color is sunlight? Visible light generally is from 390 nm (violet) to 720 nm (red). Visible sunlight is a mix of these colors at the intensities we see in the figure above. , with maximum eye sensitivity at 555…

  • Philosophy,  Random,  Science

    Arendt, Action, and Psychological Stuff

    I know next to nothing about Hannah Arendt except what I’ve read on Wikipedia and Reddit (archived).  Nevertheless, it sounds really cool. She defined the three human activities as labor, work and action, with two mutually exclusive spheres: the political and everything else. Arendt introduces the term “vita activa” (active life) by distinguishing it from “vita contemplativa” (contemplative life), which represents her understanding of Western society. There are only three human activities: labor, work and action. They correspond to the three basic conditions under which humans live. Action corresponds to the political actions of anyone… What’s striking to me (and I agree with it) is the stark division between the…

  • Philosophy,  Random,  Science

    “In r/badhistory, the view that technology is linear gets poked fun of every once in a while. Why is the view wrong?”

    In r/badhistory, the view that technology is linear gets poked fun of every once in a while. Why is the view wrong?  Isn’t technology linear? Also, why is the west so dominant when compared to other once great civilizations?   Are you familar with the idea of local maximums? Imagine in a low spot between two hills. You can climb either hill. Regardless off what hill to climb, you are increasing your elevation. But one of the hills will not reach as high as the other. In evolution, its called a fitness landscape. Paths of technological development can be similar. A recent question on ask historians involved the development of…

  • Happenings,  Random,  Science

    Sleeping

    Jordi Alba ”I sleep for 12 to 13 hours at night. Then I nap for two, three or four hours more. It’s one of the keys to my strength.” The more you sleep, up to some limit (maybe 8 hours, maybe 12 hours, maybe 17 hours), the more effective you are when you are awake.  I wonder if there is an “optimal” amount of sleep to awake ratio depending on what your daytime activities are.  For professional athletes (though it would depend on their sport), perhaps the optimal sleep : awake ratio is higher than average.  For intellectual activities (though this would also depend on what kind of intellectual activity:…