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Plunging test scores are a slow-moving catastrophe

207 points · 414 comments · vinni2

  1. vincent-uden · · focus · HN ↗
    This very much echoes the region of critical slowing down present in a dynamical system after its equilibrium states have disappeared due to a change in the system (a bifurcation).
    1. andsoitis · · focus · HN ↗
      restate in simple language please?
      1. vincent-uden · · focus · HN ↗
        I wanted to relate the result to well known phenomena in Dynamical systems. The value of the comment is in that relationship. But I guess I can try.

        After a saddle-node bifurcation (for example) a system is left with a region of critical slowing down. It can be thought of as the ghost of the fix point that used to exist in that region. Thus observing local phenomena in the system can make it look like the system is still stable while in reality it isn't.

        I guess the most famous example of this is global warning. As our emissions of greenhouse gases increased during the industrial revolution, the environment still seemed stable. But in reality we had already deleted the stable point around with our planets temperature oscillated.

        1. andsoitis · · focus · HN ↗
          Is your point that earth is not at a "stable point" or "stable range" but it used to be?

          Or are you talking about another system like "society" or "civilization"? Or something else altogether?

          1. Citizen_Lame · · focus · HN ↗
            Everything is a wave and there are always oscillations.
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