Those who are familiar with my blog know that one of my fields of specialty is so-called “singular optics,” the study of the behavior of light in regions where the light intensity is zero and the phase is singular. I’ve blogged about it a number of times; see, for instance, here and here.
The singularities of light form lines in three-dimensional space, and these lines can actually get tangled up, forming knots and braids in a light beam! Yesterday, I was sent a link to a nice article in Aeon Magazine introducing the concepts of singular optics and optical knots.
It’s a nice article, and worth taking a look at!