## When adding a third filter lets through MORE light

**3Blue1Brown with minutephysics: Some light quantum mechanics.** “This is a simple primer for how the math of quantum mechanics, specifically in the context of polarized light, relates to the math of classical waves, specifically classical electromagnetic waves.”

**minutephysics with 3Blue1Brown: Bell’s Theorem: The Quantum Venn Diagram Paradox.** “This video is about Bell’s Theorem, one of the most fascinating results in 20th century physics. Even though Albert Einstein (together with collaborators in the EPR Paradox paper) wanted to show that quantum mechanics must be incomplete because it was nonlocal (he didn’t like “spooky action at a distance”), John Bell managed to prove that any local real hidden variable theory would have to satisfy certain simple statistical properties that quantum mechanical experiments (and the theory that describes them) violate. Since then, GHZ and others have managed to extend the theoretical work, and Alain Aspect performed the first Bell test experiment in the late 1980s.”