• Most common misconceptions in popular physics

      Somewhere in an alternative Universe, based on MWI, I became a genius in physics. But in our Universe, I just read professional publications in physics, trying to keep myself up to date, meanwhile working as pizza delivery guy as DBA. Because of a slightly deeper knowledge of the subject it is almost impossible for me to watch the Discovery channel and other popular TV shows and the YouTube videos. I see nothing but oversimplifications, lies, and half-truths and can’t enjoy the shows.

      I decided to compile a list of the most popular misconceptions. And the winner is...., or course, this one:

      The Big Bang


      Usually it is pictured like this:

      image
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    • Naïve Math: the Mendocino motor and Earnshaw's theorem

      • Tutorial

      The problem statement


      I was surfing the Internet the other day and a rather curious thing caught my mind: the Mendocino motor. It’s an extremely low-friction bearing rotor: the original one had a glass cylinder hanging on two needles, but the modern ones use magnetic suspension. It’s a brushless engine: the rotor has solar batteries attached to it, which generate current for the coils wrapped around the rotor. The rotor spins in a fixed magnetic field, the solar batteries getting exposed to the light source one after the other. It’s a rather elegant solution that’s very possible to recreate at home.

      Here’s the video that explains how it works (in Russian):


      But this video had another curiosity even stronger than the engine itself. In the video description Dmitry Korzhevsky writes: “You CAN’T replace the side support with a magnet! Don’t ask me about this anymore!”
      I LOVE the 'impossible' word!