Since two decades, 9 simple lines summarize modern physics, i.e., the combination of general relativity and the standard model, with massive mixing Dirac neutrinos. These 9 lines provide a complete description of motion, describing precisely all experiments and everything that happens with full precision. However, the origin of the last 4 lines – with all their apparently "arbitrary" choices for elementary particles, gauge interactions, and fundamental constants – is not understood. Therefore, the 9 lines are not unified.

In contrast, the strand tangle model is unified: a single fundamental principle implies all 9 lines describing modern physics. Inspired by Dirac, Battey-Pratt, Racey, and Kauffman, strands of Planck radius define the quantum of action ħ and explain and deduce the observed elementary particles, gauge interactions, curved space, least action, and fundamental constants, eliminating all alternatives.