Quantum Tunneling At Home

Transcript

in classical physics if an object hits an impenetrable barrier it will always bounce off of it but in quantum mechanics if the impenetrable barrier is thin enough then the object has a non-zero probability of ending up on the other side so what that means is on a quantum scale sometimes electrons can just go through stuff you can actually see a great analog of this using a glass of water notice that as i hold the glass sideways you can see my fingers easily on the other side of the glass but when i turn the glass upright suddenly the sides of the glass become like a mirror you can't see anything outside of it so in this case the boundary is actually the air around the outside of the cup now watch what happens if i press really hard and try to reduce that air layer in between my finger and the glass to as small as possible it turns out that you actually can start seeing my finger so the photons from my finger can actually quantumly tunnel through that boundary layer of air and get to the camera