For simplicity, assume $G$ is simple, compact, connected, and simply-connected. The Chern-Simons action for a non-abelian structure group $G$ on a trivial bundle with closed base manifold is given by $$S \propto \int_M\kappa(A \wedge dA + \frac{2}{3}A\wedge A \wedge A)$$ where $\kappa$ is the Kil...

The recent discovery of a molecule that mimics the Sierpinski gasket has spurred headlines identifying it as the first fractal scientists have found in nature. I find these claims highly dubious because it's either entirely impossible for a real fractal to be realized in nature or tons of other s...

Say we have the following mask (I drew it myself on paint): I asked myself if it is possible to know the form of the image generated on a screen after the mask or know the electric field generated after the mask. I went on research and on some optics books and the closest I got was the Babinet's...