Things are conserved when there's a corresponding symmetry; this is Noether's Theorem.[1] I won't pretend to understand half that article, but here's a video[2]

Things are conserved when there's a corresponding symmetry; this is Noether's Theorem.[1] I won't pretend to understand half that article, but here's a video[2] on it. [1]: https://en.wikipedia.org/wiki/Noether%27s_theorem https://en.wikipedia.org/wiki/Noether%27s_theorem [2]: https://www.youtube.com/watch?v=04ERSb06dOg https://www.youtube.com/watch?v=04ERSb06dOg