James Lockwood

Built an FDTD Maxwell solver from scratch and rendered 45 seconds of it. What you’re watching: A plane EM wave hits a PEC barrier with two slits 90 cells apart. λ = 26 cells. The slits diffract. The beams interfere. Fringes form. Then a biconvex dielectric lens (ε = 3.8) refracts the transmitted field and partially focuses it. Young’s double-slit experiment. Fresnel diffraction. Snell’s law refraction. All emergent. None of it coded in it falls out of four update equations on a 480×480 Yee grid. This is what Maxwell’s equations actually look like when you let them run.