image/svg+xml Kepler's 1st law Kepler's 1st law Cell decomposition of torus; ←Euler Characteristic; Gauss-Bonnet formula Cell decomposition of torus; ←Euler Characteristic; Gauss-Bonnet formula = V E + F 2 π = M K d A Yang-Baxter equation Yang-Baxter equation R 12 R 23 R 12 = R 23 R 12 R 23 = c 1 c 2 ɸ A · d x A · d x = ɸ 1 c 1 c 2 150="150" />

Portal Community (b. 2020)

The wall, 2020

If one wants to summarise our knowledge of physics in the briefest possible terms, there are three really fundamental observations: