Home▸Physics & Mechanics▸Blackhole Ring: Photon Geodesics & the Photon Sphere (2D)

Blackhole Ring: Photon Geodesics & the Photon Sphere (2D)

2D Schwarzschild ray tracer: light rays are integrated along the real null-geodesic orbit equation around a black hole, splitting by impact parameter into captured, photon-ring and escaping paths.

Physics & Mechanics2DModerate60 FPS📱 Mobile-adapted⇄ 3D version

The 3D original renders a decorative particle swirl labelled "gravity" rather than any real light-bending; this 2D companion instead fires a beam of light rays and integrates each one along the exact Schwarzschild null-geodesic equation, so what you see — rays falling past the horizon, rays looping the photon sphere to trace the ring, and rays escaping after a real deflection — is the actual physics the title implies.

⚙ Under the hood

RK4-integrated photon geodesics in the Schwarzschild metric (G=c=1), classifying each ray by impact parameter against the critical value b_crit = 3√3·M.

schwarzschild metricnull geodesicphoton spheregravitational lensingevent horizonrunge-kutta

2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install