In this video I show you what a hidden variable is and then show you a proof of Bell's Theorem that shows how we know that hidden variables don't exist in quantum mechanics. Some of the information in this video was adapted from DrPhysicsA (https://www.youtube.com/watch?v=qd-tKr0LJTM). I highly recommend his channel for more in depth physics subjects. Get Your Experiment Box Here: https://theactionlab.com/ Checkout my experiment book: https://amzn.to/2Wf07x1 Follow me on Twitter: https://twitter.com/theactionlabman Facebook: https://www.facebook.com/theactionlabofficial/ Instagram: https://www.instagram.com/therealactionlab/ Watch other popular videos from my channel Gömböc—The Shape That Shouldn't Exist https://www.youtube.com/watch?v=rvVF5QWSYF4 Shooting a Nerf Gun Backwards While Driving At The Bullet's Speed Forward https://www.youtube.com/watch?v=436i_cTdtVo Superhydrophobic Knife Slices Water Drops in Half https://www.youtube.com/watch?v=Ls_ISb7lG-I Real-Life Invisibility Cloak Can Hide Anything! How Does It Work? https://www.youtube.com/watch?v=_miP7-VrIXU What's Inside the Worlds' Fastest Heat Conductor? https://www.youtube.com/watch?v=OR8u__Hcb3k Can You Use Umbrellas Instead of a Parachute? https://www.youtube.com/watch?v=zm_7txMrG5U Opening a Bottle of Liquid Nitrogen Under Water! https://www.youtube.com/watch?v=pXlJMTx4kW4 Warning: DO NOT TRY—Seeing How Close I Can Get To a Drop of Neutrons https://www.youtube.com/watch?v=jAgBiFWd-yA *Any experiment you try is at YOUR OWN RISK. The Action Lab assumes no responsibility for any injury if you attempt anything you see in this video or on The Action Lab channel.