This video was sponsored by Screen Australia and Google Australia through the SkipAhead Initiative. Thank you Kathy for the beautiful animations! https://kathysarpi.com/ Part 2: https://www.youtube.com/watch?v=tHfGucHtLqo If you want to do this experiment at home, you can! It's very simple. All you'll need is: - a weak red laser pointer (the type in cat toys are generally safe) - polarizing film or polarizing filter. If you have polaroid glasses or certain camera ND filters you may already have this. Otherwise it's available on amazon - half waveplate (the plastic thing) is this one: https://www.edmundoptics.co.uk/f/polymer-retarder-film/14827/ (λ/2 Retarder Film (WP280)) - You don't need calcite, but if you want to play with it, you can find it on etsy usually. Look for a sample that's exceptionally clear