What the bosons are
In this instantiation, "bosons" are not extra fields on $X$; they are the ambient connection, curvature, and torsion data on $Y^{14}$, seen through restriction and pullback.
Which components look like gauge bosons after pullback
How to derive spacetime fields $X$ can actually see.
Diagonalizing the visible adjoint geometry
A basis discipline for spectra and mass terms.
Masses for bosons without Higgs: torsion as the mass operator
How a covariant quadratic in augmented torsion becomes a 4D mass matrix.
Selection rules: why most ambient modes never become 4D bosons
Pullback is only the first gate; $(E,\Theta_E)$, physical-corner projection, and normal spectral suppression do the rest.