Modeling the Big Bang as a Five-Dimensional Explosion means that the 3-D Universe is a lightspeed shock wave containing both dilators and dilatons.
Grand Unification is obtained by proposing that dilators are always in phase with spacetime dilatons, thus minimizing the work of contraint forces.
This minimization process together with different considerations for spin zero (neutral matter and thus gravitation susceptible) and non-zero spin particles (electromagnetism susceptible).
These two species of particles couple with hypersuperficial (3-D surface) dilatons and volumetric (4-D volume) dilatons.
Hypersuperficial dilators can be displaced but it k-vector is defined by the perpendicular to the hypersuperficial Universe.
Volumetric dilators can change their k-vector through interaction and thus travel through the 4-D Univese freely.
The difference in response to the interference process explains the difference in intensity between Gravity and Electromagnetism.
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