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I. Fields & Ordering
This appendix lists all minimal equations and rule items (Sxx-?) in ascending code order. Each entry provides a short name, eqn (canonical form), anchors (pointers to sections in the main text), and kind (strong / weak / identity / procedure / guideline / metric / criterion).II. Inventory (sorted by code)
- S10-0 Mother Form & Writing Template
- eqn: Form: A[q] = B; weak template weak= inner_V[w, A[q]] = inner_V[w, B]
- anchors: Chapter 1 I–III
- kind: definition
- S20-1 Arrival Time (General Form)
- eqn: T_arr = ( ∫_{gamma(ell)} ( n_eff / c_ref ) d ell )
- anchors: Chapter 2 I–III
- kind: identity
- S20-2 Segment Additivity of Arrival Time
- eqn: If gamma = ⋃_k gamma_k, then T_arr(gamma) = ( ∑_k T_arr(gamma_k) )
- anchors: Chapter 2 IV
- kind: identity
- S20-3 Constant-Factoring Convention
- eqn: If c_ref is constant along gamma(ell), then T_arr = ( 1 / c_ref ) * ( ∫_{gamma(ell)} n_eff d ell )
- anchors: Chapter 2 II
- kind: identity
- S30-1 Constitutive Mapping for Effective Index
- eqn: n_eff def= F_map( T_fil, TensionGrad, rho, ... )
- anchors: Chapter 3 I–II
- kind: definition
- S30-2 First-Order Approximation Family (Linearized Example)
- eqn: n_eff approx a0 + a1 * T_fil + a2 * div[TensionGrad] (coefficients constant or slowly varying within the domain)
- anchors: Chapter 3 III–IV
- kind: guideline
- S30-3 Differentiability & Applicability of the Mapping
- eqn: grad_{args} F_map exists and is bounded; failure regions are marked by the constraint set D_forbid
- anchors: Chapter 3 V
- kind: criterion
- S40-1 Steady Minimal Equation for the Tension Field
- eqn: - div( K_T * grad[T_fil] ) + alpha * T_fil = S_src on Ω
- anchors: Chapter 4 II
- kind: strong
- S40-2 Unsteady Minimal Equation for the Tension Field
- eqn: ∂_t T_fil - div( K_T * grad[T_fil] ) + alpha * T_fil = S_src on Ω × (0, T]
- anchors: Chapter 4 II–III
- kind: strong
- S40-3 Weak Form for the Tension Field
- eqn: weak= inner_Ω[w, ∂_t T_fil] + ( ∫_Ω grad[w] • ( K_T * grad[T_fil] ) d V ) + inner_Ω[w, alpha * T_fil] = inner_Ω[w, S_src] + B[w]
- anchors: Chapter 4 IV
- kind: weak
- S50-1 Continuity Equation
- eqn: ∂_t rho + div( J ) = S_src
- anchors: Chapter 5 I–II
- kind: strong
- S50-2 Flux Definition (Advection–Diffusion Paradigm)
- eqn: J def= - D * grad[rho] + U * rho
- anchors: Chapter 5 II–III
- kind: definition
- S60-1 Boundary Condition Template
- eqn: T_fil|_{∂Ω_D} = g_D; nu • ( K_T * grad[T_fil] )|_{∂Ω_N} = g_N
- anchors: Chapter 6 II–III
- kind: procedure
- S60-2 Initial Condition Template
- eqn: T_fil(x, 0) = T_init(x); or, in general, q(x, 0) = q_init(x)
- anchors: Chapter 6 II
- kind: procedure
- S70-1 Variational Functional
- eqn: Lagr[q] = ( ∫_Ω ( 1/2 * grad[q] • K_T • grad[q] + 1/2 * alpha * q^2 - S_src * q ) d V ) + BC_terms
- anchors: Chapter 7 II
- kind: definition
- S70-2 Euler–Lagrange / Weak-Form Correspondence
- eqn: delta[Lagr] = 0 weak= inner_Ω[w, ∂_t q] + ( ∫_Ω grad[w] • ( K_T * grad[q] ) d V ) + inner_Ω[w, alpha * q] - inner_Ω[w, S_src] = 0
- anchors: Chapter 7 III–IV
- kind: weak
- S80-1 Coarse-Graining Closure (Subgrid Flux)
- eqn: bar_q def= avg_V[q; V] or avg_t[q; Δt]; J_sgs^q def= - K_sgs^q * grad[ bar_q ]
- anchors: Chapter 8 II–III
- kind: guideline
- S90-1 Discrete Conservation & Discrete Inner Products
- eqn: inner_h[u,v] def= ( ∑_{i} u_i * v_i * |V_i| ); ∑_{i} ( div_h F )_i * |V_i| = ∑_{faces} ( F_f • nu_f ) * A_f
- anchors: Chapter 9 II
- kind: metric
- S90-2 Discrete Arrival Time
- eqn: T_arr_h = ( ∑_i ( n_eff_i / c_ref ) * ds_i ); segment additivity T_arr_h = ( ∑_k T_arr_h^{(k)} )
- anchors: Chapter 9 III
- kind: identity
- S90-3 Assembly Consistency (Strong → Weak → Algebraic)
- eqn: M * dq/dt + K(q) = f + b; Newton linearization K(q) ≈ K(q^n) + J(q^n) * ( q^{n+1} - q^n )
- anchors: Chapter 9 IV
- kind: procedure
- S90-4 Time-Stepping Stability Bounds
- eqn: Convective bound Δt ≤ CFL * min_i( Δx_i / |u|_{max,i} ); diffusive bound Δt ≤ σ * min_i( Δx_i^2 / ( 2 * d * κ_{max,i} ) )
- anchors: Chapter 9 V
- kind: guideline
- S90-5 Boundary Priority Rule
- eqn: When value and flux are both given at the same location, prefer Dirichlet; Neumann serves only as a diagnostic term
- anchors: Chapter 9 VI
- kind: criterion
- S90-6 Error and Conservation Metrics
- eqn: E_L2 def= sqrt( ∑_i |x_i - y_i|^2 * |V_i| ); E_Linf def= max_i |x_i - y_i|; E_T def= | T_arr(x) - T_arr(y) |
- anchors: Chapter 9 VII
- kind: metric
- S90-7 Order-of-Accuracy Estimation
- eqn: p_est def= log2( E_k / E_{k+1} ), where E_k = L2_h[ q_{h_k} - q_{h_{k+1}} ]
- anchors: Chapter 9 VIII
- kind: metric
- S90-8 Numerical Realization of Statistics
- eqn: avg_t[q; Δt] ≈ ( 1 / N_t ) * ( ∑_{k=0}^{N_t-1} q^{n-k} ); avg_V[q; V] ≈ ( 1 / |V| ) * ( ∑_{c ∈ V} q_c * |V_c| )
- anchors: Chapter 9 IX
- kind: procedure
- S90-9 Regression Pass Criterion
- eqn: pass if ( L2 ≤ τ_L2 and L_inf ≤ τ_Linf ) and | T_arr - T_arr_ref | ≤ τ_T
- anchors: Chapter 9 XI
- kind: criterion
III. Quick Jump Index (by topic)
- Arrival time & paths: S20-1, S20-2, S20-3, S90-2
- Constitutive & mappings: S30-1, S30-2, S30-3
- Tension-field control equations: S40-1, S40-2, S40-3
- Continuity & flux: S50-1, S50-2
- Boundary & initial data: S60-1, S60-2
- Variational & weak forms: S70-1, S70-2
- Statistics & coarse-graining: S80-1, S90-8
- Numerics & consistency: S90-1, S90-3, S90-4, S90-5, S90-6, S90-7, S90-9
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Suggested attribution: Author: “Guanglin Tu”; Work: “Energy Filament Theory”; Source: energyfilament.org; License: CC BY 4.0.
First published: 2025-11-11|Current version:v5.1
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