Kepler’s original theory was that the orbits in the solar system were defined by polygons and their inscribed/circumscribed spheres. This seemed very attractive because at that time they knew of 6 planetary bodies and this fitted in somehow (I don’t remember exactly) into this model with nested platonic solids and the spheres around them. Then Kepler realised that the predictions of this very elegant model were worse than the heliocentric model.
So when Brahe’s observations became available he basically threw all that out and started again, to develop his wonderfully elegant laws of planetary motion based around elliptical orbits which also have the significant benefits of predicting planetary motion beautifully and were later found to be entirely derivable from Newton’s laws of motion using calculus (there is a wonderful presentation of this derivation in Spivak for anyone who is interested).
I noticed "Kepler" in the title and cool story about Kepler so now I'm mentioning it;
"Grassmannian Gravity from QED & Gauge Scattering Amplitudes: Complex Gr_C(2,4) Orbital Precession, Mercury's Perihelion, N-Body Dynamics, and Dilatant Dark Fluid (DDF) Unification in Lean 4" (2026) westurner/sustainablefactory/docs/grassmannian-gravity-from-qed-scattering-paper.md at main · westurner/sustainablefactory https://github.com/westurner/sustainablefactory/blob/main/do... :
> An arXiv-ready formal verification paper deriving planetary orbits, Mercury's 42.98 arcsec/century perihelion precession, and N-body gravitational dynamics from flat-space QED/gauge scattering amplitudes, BCJ double copy on Gr_C(2,4), and Dilatant Dark Fluid (DDF) hydrodynamics in Lean
There's already gravity that fits the Perihelion of Mercury from QED scattering (Partanen, M., and Tulkki, J. (2025). "Gravity Generated by Four One-Dimensional Unitary Gauge Symmetries and the Standard Model" / "Perihelion Precession of Planetary Orbits Solved from Quantum Field Theory"). FWIU, I've here contributed the use of Grassmanian Plückers and a Complex Grassmannian - GrC(2,4) both with and without connections to DDF Dilatant Dark Fluid (Fedi).
I had created a simple particle wave visualization tool with 3js and then on a whim AI-added a double slit and a detector screen, and I asked for Huygens-Steiner Parallel-Axis Intensity as the model to simulate superposition because of [Qian and Izadi] and then I had to keep working on that instead. First the model differencing in the simulator in JS to compare the difference in model predictions in the double-slit experiment against Pilot Wave Theory and Wigner function and then with Fraunhofer and Lean 4 and Rust and a crisp symbolic error term for each model of photonic and electronic superposition. It looks like GrC(2,4) is the most efficient model for photonic and electronic superposition, too.
"Huygens–Steiner Barycentric Coherence, Complex Gr_C(2,4) Plücker Channels, and Multi-Model Double-Slit & OAM Relative Predictive Error in Lean 4" (2026)
sustainablefactory/docs/grassmannian-huygens-double-slit-oam-paper.md at main · westurner/sustainablefactory https://github.com/westurner/sustainablefactory/blob/main/do... :
> An arXiv-ready formal verification paper uniting Qian–Izadi Huygens–Steiner parallel-axis coherence, complex Gr_C(2,4) Plücker double-slit interference, de Broglie–Bohm pilot-wave hydrodynamics, Wigner phase-space marginals, and Orbital Angular Momentum (OAM) relative predictive error in Lean
Useful to create a devcontainer with lean4 and rust. Still working through verifying the URLs of each citation to publish some of this paper series per the latest terms for AI articles.