Why Particles Change When We Watch Them

What if the Universe only "renders" when something looks at it? In this lesson we fire paintballs, flood the classroom and shoot single electrons at a fence with two slits, all inside a Minecraft classroom, to see why the double-slit experiment is the most beautiful and unsettling paradox in physics. You will learn why solid things make two stripes and waves make a zebra pattern, what happened when physicists fired one electron at a time, why a detector at the slits makes the zebra disappear, and why it is not about consciousness at all. ⏱ CHAPTERS 0:00 Does the world only render when you look? 0:22 The paradox 0:57 Scenario 1: paintballs 1:27 Scenario 2: waves and the zebra pattern 2:04 Electrons 2:28 One electron at a time 3:09 The detector and the observer effect 3:43 Not magic: what measuring really does 4:21 What it means for reality 4:45 Next: the Quantum Eraser 🔬 SOURCES A. Tonomura et al. (1989), "Demonstration of single-electron buildup of an interference pattern", American Journal of Physics 57, 117. P. G. Merli, G. F. Missiroli, G. Pozzi (1976), "On the statistical aspect of electron interference phenomena", American Journal of Physics 44, 306. R. Feynman, The Feynman Lectures on Physics, Vol. III, Chapter 1: Quantum Behavior. S. Dürr, T. Nonn, G. Rempe (1998), "Origin of quantum-mechanical complementarity probed by a 'which-way' experiment in an atom interferometer", Nature 395, 33. S. P. Walborn et al. (2002), "Double-slit quantum eraser", Physical Review A 65, 033818. 🚀 NEXT LESSON: The Quantum Eraser, erasing the path after the particle has already passed. Subscribe so you do not miss it. 💬 Before this video, did you think the particle "knows" it is being watched? Tell me in the comments. This is a fan-made educational video. Not an official Minecraft product. Not approved by or associated with Mojang or Microsoft. #doubleslit #quantumphysics #minecraft #science