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Joined 1 month ago
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Cake day: April 16th, 2026

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  • Plastic and elastic deformation are both terms used to refer to the behavior of a material under stress (such as compression, tension, or torsion).

    For an ELI5 since I don’t feel like cracking open a material science textbook or really getting more nuanced than this for a basic explanation, elastic deformation is generally reversible without permanent changes to the structure of the material, while plastic deformation imparts a permanent change.

    All materials have elastic and plastic deformation modes that can be identified based on their characteristic stress-strain curve. Generally, the linear portion of the curve at lower stresses is the elastic region, and the plastic region begins where the curve becomes nonlinear.

    For example, a wooden beam in a house will bend under normal load. As people move out of the room that beam is in, it will straighten back out- that is elastic deformation. Put too many people or some very heavy furniture in the room, though, and the beam will become permanently bent or even break altogether- that is a plastic deformation.

    Some solid books on this topic are Shigley’s Mechanical Engineering Design and Roark’s Formulas for Stress and Strain

    The colloquial use of elastic and plastic to describe certain groups of materials is based off the behaviors of these modes of deformation. E.g. elastics are stretchy and return to their original shape. If you really want to get into semantics, there are only four types of materials: metals, polymers, ceramics, and composites. Everything else is one of those 4 things.





  • Encouraging people to get the depopulation (emergency use authorization mrna) shots is also disqualifying to me

    the unforgiveable thing to me is the lack of basic first-principles reasoning and also an inability to read scientific journals criticially.

    Really telling on yourself here lol. If that was your takeaway from research around the vaccines then you lack the very competencies you find it unforgivable to lack.













  • Not exactly what you’re looking for, but this reminds me of The Quiet Year:

    The Quiet Year is a map game. You define the struggles of a community living after the collapse of civilization, and attempt to build something good within their quiet year. Every decision and every action is set against a backdrop of dwindling time and rising concern.

    The game is played using a deck of cards – each of the 52 cards corresponds to a week during the quiet year. Each card triggers certain events – bringing bad news, good omens, project delays and sudden changes in luck. At the end of the quiet year, the Frost Shepherds will come, ending the game.

    The game occupies a niche somewhere between a ttrpg and a board game.