Projective rays here describe field coefficients. Particle positions remain ordinary spatial coordinates in the infinite-dimensional containing space.

Physical premise (IDWT): Physical spacetime has infinitely many ordinary spatial dimensions plus time. Matter occupies up to ten spatial dimensions; all remaining spatial directions are unbound for every particle. Depth counts a pattern's bound spatial involvement within that space. “Observed” and “unobserved” describe an observer's access, not different kinds of dimension. Older projective and nested-geometry calculations below retain their additional hypotheses; they do not establish a separate physical manifold or compactified direction. See spatial meaning and mathematical scope.

Summary: The constrained magnetic kernel distinguishes five-dimensional null-axis polarization from six-dimensional complex-structure polarization, while the scalar-exchange bridge explicitly supplies a five-dimensional vector-channel escape route.

Same kernel, different spinor moments

Use the existing magnetic bridge: a fixed square-integrable density envelope, one uniform pure polarization, positive magnetic cost, and the leading Pauli coupling. At nonzero Fourier wavevector kk, the closed-field projector on skew matrices is

PkJ=PkJ+JPk,Pk=kkT∣k∣2.\mathcal P_kJ=P_kJ+JP_k,\qquad P_k=\frac{kk^T}{|k|^2}.

This formula is valid in either ambient dimension. Its amplitude-space rank is d−1d-1 and its isotropic angular average is (2/d)I(2/d)I on bivectors. In particular the average factor is 2/52/5 in five dimensions and 1/31/3 in six. An average projector factor is not itself a particle-depth measurement.

With ∥J∥2=−tr⁡(J2)/2\|J\|^2=-\operatorname{tr}(J^2)/2,

∥PkJ∥2=∣Jk∣2∣k∣2.\|\mathcal P_kJ\|^2=\frac{|Jk|^2}{|k|^2}.

The selected moments derived from the explicit spinors obey

J52=−I5+nnT,∣n∣=1,J62=−I6.J_5^2=-I_5+nn^T,\quad |n|=1, \qquad J_6^2=-I_6.

Therefore their directional response strengths are

∥PkJ5∥2=1−(n⋅k^)2,∥PkJ6∥2=1.\|\mathcal P_kJ_5\|^2=1-(n\cdot\widehat k)^2, \qquad \|\mathcal P_kJ_6\|^2=1.

There is a genuine zero-response direction in five dimensions. No rescaling of the coupling removes it. More generally every skew matrix in an odd-dimensional real space is singular, since det⁡J=det⁡(−J)=(−1)ddet⁡J\det J=\det(-J)=(-1)^d\det J. Thus a nonzero isotropic response for every wavevector at one fixed polarization is impossible for any odd-dimensional bivector in this kernel. Four-dimensional invertible skew matrices exist, so this parity result alone does not establish exactly six.

Envelope anisotropy changes the minimum family differently

Write f(k)=∣n~(k)∣2≥0f(k)=|\widetilde n(k)|^2\geq0 for the prescribed envelope weight, using a consistent Fourier convention, and define

W=∫f(k) dk,T=∫f(k)k^k^T dk,tr⁡T=W.W=\int f(k)\,dk,\qquad T=\int f(k)\widehat k\widehat k^T\,dk,\qquad\operatorname{tr}T=W.

After constrained field minimization, the polarization energies are

E5(z)=−g22ZB(W−n(z)TTn(z)),E6(z)=−g22ZBW.E_5(z)=-\frac{g^2}{2Z_B}\left(W-n(z)^TTn(z)\right), \qquad E_6(z)=-\frac{g^2}{2Z_B}W.

For an isotropic five-dimensional envelope, T=(W/5)I5T=(W/5)I_5, the whole CP3 polarization family still minimizes and the magnitude is (4/5)g2W/(2ZB)(4/5)g^2W/(2Z_B). For a generic anisotropic envelope with a simple lowest eigenvalue, nn instead aligns with either sign of its lowest-eigenvalue axis.

For any unit nn, the condition γ(n)z=z\gamma(n)z=z defines a complex two-dimensional eigenspace, and its normalized rays form CP1. The explicit spinor identity gives precisely these rays the prescribed nn. Hence a simple lowest envelope eigenvalue leaves two CP1 minimum families, one over each sign of the selected axis, not the full CP3. At either family, four ray directions acquire positive curvature and two remain flat. In six dimensions all six ray directions remain flat under this spin-magnetic energy for any such fixed envelope.

If the lowest eigenvalue of TT has multiplicity mm, its allowed unit vectors form Sm−1S^{m-1} and each has a CP1 ray fibre. The minimum family therefore has real dimension m+1m+1; this dimension count does not assert that the bundle is globally a product. The m=1m=1 case is the two CP1 components above, and m=5m=5 restores all of CP3.

In particular, an envelope respecting a three-visible-plus-two-unobserved split has T=diag⁡(tVI3,tHI2)T=\operatorname{diag}(t_V I_3,t_H I_2), with 3tV+2tH=W3t_V+2t_H=W. If tH<tVt_H<t_V, the minimum family has dimension three; if tV<tHt_V<t_H, dimension four; if they are equal, dimension six. This symmetry-respecting comparison is more relevant to a fixed nuclear three-plane than assuming an arbitrary five-distinct-eigenvalue envelope. The corresponding six-dimensional pure-spinor magnetic energy remains ray-independent within the stated uniform-polarization approximation. For T=diag⁡(2,2,2,1,1)/8T=\operatorname{diag}(2,2,2,1,1)/8, a separate finite-difference check gives ray Hessian (0,0,0,1,1,1)(0,0,0,1,1,1) to 4×10−84\times10^{-8}, as the dimension count predicts. The fibre argument is explicit: γ(n)2=I\gamma(n)^2=I and tr⁡γ(n)=0\operatorname{tr}\gamma(n)=0 give a two-complex-dimensional positive eigenspace. A ray in it has n(z)⋅n=1n(z)\cdot n=1; the already proved unit norm of n(z)n(z) forces n(z)=nn(z)=n. Rotational covariance gives the same smooth two-real-dimensional fibre over every axis.

An exact axis-weight quadrature with five-dimensional weights (5,4,3,2,1)/15(5,4,3,2,1)/15 yields the ray Hessian eigenvalues

(0,0,815,1615,2415,3215),\left(0,0,\frac8{15},\frac{16}{15},\frac{24}{15},\frac{32}{15}\right),

for energy normalized by g2/(2ZB)=1g^2/(2Z_B)=1. Numerical derivatives reproduce these values. With six-dimensional weights (6,5,4,3,2,1)/21(6,5,4,3,2,1)/21 every ray Hessian eigenvalue is zero analytically and below 1.2×10−81.2\times10^{-8} in the finite-difference calculation.

This is a structural prediction of two competing kernels, not a fit of their coupling constants. The five-dimensional null axis and the envelope are explicit variables; no V1 choice of S5 or CP2 spatial base was used.

Relation to the spectral discriminator

The spectral comparison assumed an isotropic unrestricted bivector cost. For an isotropic envelope, the integrated magnetic projector merely rescales that coupling, preserving the corresponding gap multiplicities. For an anisotropic envelope the selected field is generally not proportional to JJ.

Consequently the six-dimensional frozen-field excited gaps need not remain triply equal for an anisotropic envelope, even though its joint field-plus-ray minimum family remains CP3. These are different statements. Do not demand the isotropic-source singlet-triplet spectrum of every anisotropic magnetic preparation.

The existing scalar-exchange bridge supplies the escape channel

The operator-class restriction is substantive in the project's other source proposal. In five dimensions the sixteen Hermitian matrix directions are the identity, five γa\gamma_a, and ten bivectors HabH_{ab}, orthogonal with trace norm four. For any Hermitian density matrix ϱ\varrho, write

N=tr⁡ϱ,va=tr⁡(ϱγa),bab=tr⁡(ϱHab).N=\operatorname{tr}\varrho,\quad v_a=\operatorname{tr}(\varrho\gamma_a), \quad b_{ab}=\operatorname{tr}(\varrho H_{ab}).

Completeness gives

4tr⁡(ϱ2)=N2+∣v∣2+∣b∣2.4\operatorname{tr}(\varrho^2)=N^2+|v|^2+|b|^2.

The same explicitly assumed Gaussian scalar-exchange reduction used in the scalar bridge therefore becomes

EG=κ2(N2−tr⁡ϱ2)=3κ8N2−κ8(∣v∣2+∣b∣2).E_G=\frac\kappa2\left(N^2-\operatorname{tr}\varrho^2\right) =\frac{3\kappa}{8}N^2-\frac\kappa8\left(|v|^2+|b|^2\right).

It supplies both a vector and a bivector channel. Dropping the vector channel would not preserve that exchange identity. For a pure ray, S(b)+v⋅γ=4zz†−IS(b)+v\cdot\gamma=4zz^\dagger-I, exactly the operator that evades the five-dimensional bivector-only spectral no-go.

Thus the leading Pauli/magnetic proposal and the full scalar-exchange proposal do not have the same dimension-discrimination power. No spectral exclusion of the full five-dimensional exchange competitor has been proved. The existing exchange caveats—Gaussian closure, statistics, normal ordering, and absence of exact one-particle two-body self-interaction—remain unchanged.

Physical scope and next test

This calculation tests a concrete part of the response kernel already in the archive. It omits orbital magnetic energy, electric response, radiation, spatial profile relaxation, nonuniform polarization, and the nucleus. Anisotropy should next be generated by the coupled envelope/nucleus solution, rather than chosen only as a diagnostic Fourier weight.

The useful discriminant is polarization response to controlled envelope anisotropy, or a preparation-resolved directional magnetic response. Whether the electron exhibits either specified response still needs a derived observable map. The mathematics does not identify an electron from CP3 geometry or an averaged cloud alone.

Verification

dimensional_magnetic_kernel_checks.py performs 500 runtime checks, including kernel projection, directional responses, envelope minimization, the CP1 family, numerical Hessians, and the mixed-density exchange identity. Evidence: dimensional-magnetic-kernel.json.