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Part 8· Appendix C

Appendix C — Discrete–Continuous Correspondence Dictionary

This appendix provides a unified dictionary relating the discrete constructions of the RelationWorld theory to their counterparts in continuous differential geometry and gauge theory.


C.1 Main Dictionary

#Discrete (this theory)Continuous (gauge theory / Riemannian geometry)
1Finite set VV, $V
2Edge set EtE_tTangent bundle structure
3Symmetric weight Wt(i,j)W_t(i,j)Riemannian metric gμνg_{\mu\nu}
4Edge group element gt(i,j)Gg_t(i,j)\in GConnection 1-form AΩ1(M,g)A\in\Omega^1(M,\mathfrak{g})
5Gauge group G=GV\mathcal{G}=G^VGauge transformation group Map(M,G)\mathrm{Map}(M,G)
6Gauge action gth(i,j)=h(i)gt(i,j)h(j)1g_t^h(i,j)=h(i)g_t(i,j)h(j)^{-1}Ag=gAg1+gdg1A^g=gAg^{-1}+g\,dg^{-1}
7Triangle holonomy Ωt()\Omega_t(\triangle)Curvature 2-form FA=dA+AAF_A=dA+A\wedge A
8Scalar curvature ωt()=dG(Ωt,e)2\omega_t(\triangle)=d_G(\Omega_t,e)^2FA2\|F_A\|^2
9Degree dt(i)d_t(i)Volume element gdnx\sqrt{g}\,d^nx
10Volume volt(S)\mathrm{vol}_t(S)Riemannian volume Vol(U)\mathrm{Vol}(U)
11Cut cutt(S,Sˉ)\mathrm{cut}_t(S,\bar S)Boundary area Area(U)\mathrm{Area}(\partial U)
12Conductance ϕt(S)\phi_t(S)Cheeger constant h(M)h(M)
13Fruit FF (ϕt(F)θ\phi_t(F)\le\theta)Metastable sub-manifold
14Stem St\mathcal{S}_tThin neck / bridge region
15Boundary coupling bF,t(i)b_{F,t}(i)Normal flux through U\partial U
16Door Στ(F,t)\Sigma_\tau(F,t)Uhlenbeck singular set {p1,,pL}\{p_1,\ldots,p_L\}
17Door energy epe_pBubble energy limr0Br(p)FA2\lim_{r\to0}\int_{B_r(p)}\lvert F_A\rvert^2
18Door threshold τ\tauEnergy quantum ϵ0\epsilon_0
19Kernel F=FΣF^\circ=F\setminus\SigmaPunctured manifold M{p1,,pL}M\setminus\{p_1,\ldots,p_L\}
20Flattening energy EF(h)\mathcal{E}_{F^\circ}(h)Yang--Mills energy MFA2dV\int_M\|F_A\|^2\,dV
21Optimal gauge hh^*Coulomb gauge / Uhlenbeck gauge
22Canonical connection [A][A_\infty]Limit connection (gauge class)
23Existence ([A],Σ,e)([A_\infty],\Sigma,\mathbf{e})Point in Uhlenbeck compactification
24Moduli space M(F,Σ)\mathcal{M}(F,\Sigma)Moduli space of connections
25World Wt\mathfrak{W}_tSpacetime with gauge field
26Normalised Laplacian Lt\mathcal{L}_tLaplace--Beltrami operator Δg\Delta_g
27Random walk PtP_tHeat kernel / Brownian motion
28Escape time TescT_{\mathrm{esc}}Mixing time / first exit time
29YM gradient flow h˙=E\dot h=-\nabla\mathcal{E}Yang--Mills flow tA=dAFA\partial_t A=-d_A^*F_A
30Lojasiewicz convergenceSimon's convergence theorem

C.2 Correspondence of Theorems

Discrete TheoremContinuous Analogue
A (Energy isolation)Cheeger inequality
B (Finiteness of doors)Uhlenbeck compactness (LE/ϵ0L\le E/\epsilon_0)
C (Self-interpretation)Internal boundary data determines singular set
D (Metastability)Spectral gap \Leftrightarrow mixing time
E (Curvature localisation)Removable singularity / regularity away from bubbles
F (Spectral stability)Stability of Cheeger constant under metric perturbation
G (Door stability)Stability of singular set under connection perturbation
H (Flow stability)Lojasiewicz--Simon gradient inequality \Rightarrow convergence

C.3 Axiom Correspondence

Discrete AxiomContinuous Counterpart
A0: Compact Lie group GGStructure group of principal bundle
A1: Finite node set VVCompact base manifold MM
A2: Time set T\mathbb{T}Time parameter in evolution equations
A3: Fruit threshold θ\thetaCheeger constant threshold
A4: Door threshold τ\tauEnergy concentration quantum ϵ0\epsilon_0
A5: Intrinsic data axiomBoundary trace theorem (Sobolev)

C.4 Key Differences

The discrete theory is not merely a discretisation of the continuous theory. Key structural differences:

  1. Finite-dimensionality: all spaces are finite, so existence and compactness results are immediate (no functional analysis needed).

  2. No regularity issues: there are no Sobolev spaces, no weak solutions, no regularity theory. All functions are finitely specified.

  3. Exact computations: cohomology is computed by finite matrix algebra, not by solving PDEs.

  4. Combinatorial conductance: replaces the geometric Cheeger constant, but retains the same spectral relationship (discrete Cheeger inequality).

  5. Doors vs. bubbles: discrete doors are individual nodes; continuous bubbles are idealised points with concentration measures. The discrete version is inherently regularised.