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Tangent coverage, forms and horizontal operations

Shadow Theory and the Wilson Yang–Mills Construction: A Source–Readout Reconstruction

Tangent coverage, forms and horizontal operations

Let d0φ be the edge cochain (d0φ)e = φy −φx. At the identity readout, differentiating rx(t) = exp(tφx) and Ae(t) = exp(tae) gives

p(φ, a) = a + d0φ,
j(u) = (0, u),
pj = I.
Source page 510.
Searchable transcription
p(φ, a) = a + d0φ,
j(u) = (0, u),
pj = I.

The kernel is exactly {(φ, −d0φ)}: this follows directly by solving p(φ, a) = 0. Oriented boundary cancellation gives d1d0 = 0, hence d1p(φ, a) = d1a. This kernel is infinitesimal frame redundancy; it is distinct from any subsequent physical gauge or harmonic restriction in the supplied construction.

Theorem A.1 (Operator and quadratic-form recovery). For a target operator T : H1 →H2 on the specified finite cochain spaces, put TZ = j2Tp1. Then

p2TZ = Tp1,
TZj1 = j2T.
Source page 510.
Searchable transcription
p2TZ = Tp1,
TZj1 = j2T.

Compositions are preserved: SZTZ = j3STp1. A symmetric target form with matrix Q instead pulls back as QZ = p∗Qp. Its nullspace is p−1(ker Q), and its restriction to the section is the original form.

Proof. Insert piji = I in the two intertwining identities and the composition. For the form, its value on v, w is ⟨pv, Qpw⟩by the definition of the adjoint. Thus its radical consists precisely of v for which Qpv = 0, since p is onto. In particular every vertical vector is null. Taking v = ju, w = jv′

recovers the original form. The transported section inner product makes j an isometry. It does not assert that j is an isometry for an unrelated ambient inner product or that jTp equals p∗Tp.

For example the source stationary identity

Qc = T ∗QfT + b(I −PT)∗(I −PT)
Source page 510.
Searchable transcription
Qc = T ∗QfT + b(I −PT)∗(I −PT)
pulls back to
p∗
cQcpc = T ∗
Zp∗
fQfpfTZ + b(pc −PpfTZ)∗(pc −PpfTZ).
Source page 510.
Searchable transcription
pulls back to
p∗
cQcpc = T ∗
Zp∗
fQfpfTZ + b(pc −PpfTZ)∗(pc −PpfTZ).
This follows by substitution and pfTZ = Tpc. Replacing the last readout difference by I −PZTZ
on the whole redundant space changes the form on vertical directions. Any positive lower bound
is retained only on the original restricted space or its isometric section, with the original norm and
restrictions.
For a differentiable finite-lattice curve let kx =  ̇rxr−1
x . Exact matrix differentiation gives
Source page 510.
Searchable transcription
This follows by substitution and pfTZ = Tpc. Replacing the last readout difference by I −PZTZ
on the whole redundant space changes the form on vertical directions. Any positive lower bound
is retained only on the original restricted space or its isometric section, with the original norm and
restrictions.
For a differentiable finite-lattice curve let kx =  ̇rxr−1
x . Exact matrix differentiation gives
 ̇Ue = r−1
x (  ̇Ae −kxAe + Aeky)ry.
Source page 510.
Searchable transcription
 ̇Ue = r−1
x (  ̇Ae −kxAe + Aeky)ry.

Every target tangent he ∈TUeG lifts, for any differentiable frame curve, by

 ̇Ae = rxher−1
y
+ kxAe −Aeky.
Source page 510.
Searchable transcription
 ̇Ae = rxher−1
y
+ kxAe −Aeky.
Indeed differentiate Ae = rxUer−1
y ; this also proves group-tangent membership. At fixed target
input the two frame terms are still required. The flat target configuration at arbitrary frames is
Ae = rxr−1
y .
Let P be any actual tagged source predictor from fine links to coarse links on its stated domain.
With coarse frames s, define
Source page 510.
Searchable transcription
Indeed differentiate Ae = rxUer−1
y ; this also proves group-tangent membership. At fixed target
input the two frame terms are still required. The flat target configuration at arbitrary frames is
Ae = rxr−1
y .
Let P be any actual tagged source predictor from fine links to coarse links on its stated domain.
With coarse frames s, define
Bb = syP(π(r, A))bs−1
z ,
b : y →z.
Source page 510.
Searchable transcription
Bb = syP(π(r, A))bs−1
z ,
b : y →z.

Then πc(s, B) = P(πf(r, A)) identically. On a smooth branch, for coarse rates l =  ̇ss−1,

 ̇Bb = syDPU[h]bs−1
z
+ lyBb −Bblz.
Source page 511.
Searchable transcription
 ̇Bb = syDPU[h]bs−1
z
+ lyBb −Bblz.

Differentiating the coarse readout cancels the last two terms and recovers DPU[h]. The proof uses the actual predictor, with its routes, minimizers, fallback tags and finite stencil. A multivalued target branch is lifted as a tagged relation; no new selection is introduced. Norm estimates transfer with the transported color-block norms on fixed-frame or horizontal derivatives. They do not bound arbitrary unbounded frame rates.

Source: Shadow Theory and the Wilson Yang–Mills Construction: A Source–Readout Reconstruction. Both papers belong to one Zenodo record. No external funding.