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Gravity in n spatial dimensions

What you are seeing: a test particle orbiting a heavy mass under the generalized force F=kr/rd1\vec F = -k\,\vec r/r^{d-1} that you would get if space had dd rather than 33 spatial dimensions. Drag dd from 2 to 6 and watch what happens to the orbit. Only d=3d = 3 gives the closed Kepler ellipse; d=2d = 2 precesses, d=4d = 4 is marginal, d5d \ge 5 plunges

Figure 1. Orbit traces under the generalized central force; the trail accumulates many revolutions. Method: velocity-Verlet on the inverse-power central force.
dimension d3.00
initial r₀1.00
eccentricity f1.05
trail length1500

WHAT TO TRY

  • Vary each control and watch the rail readouts respond.
  • Compare the diagnostic plot against the live scene.