• 4 Posts
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Joined 2 years ago
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Cake day: June 20th, 2023

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  • Makes me think of this upcoming competition to find fossils that are not surrounded by the rocks that science expects.

    I suspect a lot of people who believe (some subset of) the crazy nonsense are actually science inclined. But we (often/used to) teach science as about great people heroically defying the consensus and triggering a paradigm shift that changes the world. And that looks a lot more like vaccine denialism than pipetting samples for 50 hours. Some of the community spaces are clearly interested in thinking about the world, and there’s a self-isolating effect of asking someone

    “Why is there a tree that’s fossilized across 5 different epochs of bedrock?”

    and being told you’re a crank. Then layer on the grifters.

    So yes; do remember to talk people through the facts before labeling them a conspiracy theorists, and focus on the shared amazement at how weird/complicated/nuanced the data is. Ask lots of questions!




  • I think I understand the claim: the energy cost of keeping heat outside of a box should be proportional to the surface area, not how much stuff is in the box.

    This is true; but only once the contents of the box are already cold. I think what it neglects is that the stuff you are putting in is not already 0 K (or your fridge temp), it is usually much warmer. So the fridge must work rather hard to pump all the heat you add back out. (Incidentally, the fridge has an even harder job if the volume of the fridge container is bigger, since there are more places for the heat to hide/cluster.)

    We see the opposite with old fashioned fridges (an insulated box that you put ice into, and removed the water when it melted) or modern coolers. By making an insulated box, you make the interior become the average temperature of the stuff inside. To make the stuff inside cold, you must add something much colder to bring down that average, like a pack of ice. It’s pretty hard to get 0K stuff on earth, so many things to bump into, hence very hard to use refrigeration to get things down to 0K.

    You might also be tempted by a selective insulator, that keeps hot stuff out but lets fast moving particles inside escape (so that the contents become cold). This is a classic thought experiment! Maxwell’s demon. It turns out that any such intelligent barrier will itself need energy.


  • I am pretty sure the base state isn’t 0K, it’s whatever the average temperature around the object is. If you have a universe that is 10^4 K everywhere, then objects will tend to that temperature. Because the earth is actually quite hot compared to 0 K, your fridge very much is constantly using energy to keep the extremely hot outsides from warming the inside. It would get easier if the earth was colder.











  • I personally don’t understand the logic of this symbolic act of protest, but I often don’t understand how protest is supposed to function. It did pull more attention towards gaza, and attention is everything.

    Would a better protest be to keep the invite, but plaster the space with material about the genocide? Let the person quit if this offends them (which would probably be a more sympathetic headline and just as newsworthy) and make a story out of the performance if they don’t (which should be very photogenic).


  • I agree that the first panel is off; I would replace it with “I’m going to work on my house because I want it to be the best house it can be”, or something similar.

    And, at least for democracies (or similar), one of their bigger failure modes is that people:

    1. don’t feel like they (do/can/should) contribute to the place they live;
    2. do not value the work that others do for the place and community;
    3. take for granted the natural resources, and don’t safeguard them for the future.

    Consider how it is absurd for a normal person to run for public service, and how air quality has plummeted in so many places. I think it could be healthy to be proud of a group project you participated in. It’s a bit sad that countries/states/cities/neighborhoods so often fail to be such projects.

    (Which I guess is all to say that we should gatekeep patriotic pride. That’s a weird stance I’ve landed in.)