Spinning Neutron Star work in progress

Each step adds one effect. The white ghost grid shows where the grid was one step earlier, so you see exactly what the new effect moves. Guided steps through by itself · keys 0–8.

A teaching viewpoint: real observers are light-years away. From far away the image settles to the "view from infinity": the same physics, just smaller and with less perspective.

Default star: spin 716 Hz (J1748−2446ad, the fastest known pulsar). The mass, radius, inclination and tilt are assumed (1.4 M☉, 12 km, 62°, 48°).

Blue wireframe: grid-line hue shows the Doppler shift of a 490 nm reference line (bluer = approaching). Wireframe brightness is a display of the bolometric g⁴ factor, compressed as (g⁴)^0.4 so both limbs stay visible. The hot-cap colours and the brightness curve use the true, uncompressed g⁴. The thermal style is exact: a blackbody at gT, i.e. g³ per frequency. The hot caps use NASA's brightness scale (yellow = 1 = the cap seen face-on with no relativity). Magnetic field: a rotating vacuum dipole with retarded fields (Deutsch 1955), whose lines sweep back toward the light cylinder c/Ω. Light time enters twice, with two neighbouring chips. Retarded B field (light-time twist) changes the field itself: changes spread out at c, so the lines twist, with radiation beyond c/Ω (vacuum) or a winding wind (plasma). Light-travel time (what you see) only changes when you see each piece, as if the lines glowed. Switch both off for an untwisted, instantly seen field. Which model is physical? The vacuum dipole is the textbook starting point, not the end state. A real pulsar fills its magnetosphere with plasma (Goldreich & Julian 1969). Its currents open every field line that reaches the light cylinder into a striped wind, with a current sheet beyond c/Ω (Contopoulos et al. 1999; Spitkovsky 2006; Bogovalov 1999). That also moves where the light comes from: radio from the open lines above the polar caps, pulsed γ-rays from the current sheet just outside the light cylinder. The plasma model here is a schematic built from those solutions, not a numerical simulation. Near the star it uses the Schwarzschild dipole shape (Wasserman & Shapiro 1983). The lines are seen through the same light bending and light-travel delay as the surface. A real pulsar's plasma-filled (force-free) magnetosphere opens the field lines at the light cylinder (Spitkovsky 2006). Literature: docs/NEUTRON_STAR_LITERATURE.md.