Why particles weigh what they weigh

Physics has never explained why a particle weighs what it weighs. The electron has its mass, the proton is 1,836 times heavier, and the muon, an electron-like particle that lives about two millionths of a second, is 207 times heavier. The Standard Model measures these numbers and writes them in.

RSI offers a different picture. If the universe is a physical medium under tension, particles are knots in it, and knots have rules. A knot can only be so tight before the medium cannot hold it, and only so loose before it slips undone. Between those limits only certain shapes hold, just as a guitar string under tension can sound only certain notes.

The known particles fall into families that match the knots RSI allows. Leptons, such as the electron, muon and tau, are single 720-degree loops, with the electron as the ground state and the muon and tau as the same loop wound tighter. Baryons, such as the proton and neutron, are braids of three loops. Mesons are a loop bound to its mirror image, which is why they live so briefly. The W and Z bosons are momentary compressions of the medium that relax at once into lighter knots, and the Higgs boson is the medium itself, rung hard enough to sound.

The proton's mass follows from its braid: 6π⁵ ≈ 1836.12 electron masses, within 19 parts per million of the measured ratio. The three lepton masses are bound together by a geometric relation that RSI reads as the signature of three-dimensional space. The open task is to derive the tau's mass from the medium. If that succeeds, the muon's mass follows from it, and the whole charged lepton family is accounted for.