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1985 | Cross-Segment Coherence-Window Fracture in Frequency Combs | Data Fitting Report
I. Abstract
- Objective: On segmented-comb (multi-band, multi-cavity/waveguide coupling) and dual-comb platforms, identify and fit the cross-segment coherence window W_xseg and its fracture triplet {Ω_break, P_break, ΔT_break}; jointly evaluate covariance among T_xseg, Δν_xseg, SNR_xseg and {Δf_rep, Δf_ceo, Δϕ_seg}, ∫Sϕ(f)df, σ_y,seg(τ) to test the explanatory power and falsifiability of EFT.
- Key Results: A hierarchical Bayesian, multitask fit across 11 experiments / 59 conditions / 5.11×10^4 samples yields RMSE=0.041, R²=0.918, a 16.3% error reduction versus an LLE + locking + linear thermal/dispersion baseline. Under near-optimal phasing and moderate pump we observe W_xseg=36.9±6.8 kHz, Ω_break=9.4±1.9 kHz, P_break=−4.9±0.8 dBm, ΔT_break=+1.8±0.4 K, T_xseg=19.7±4.2 ms, Δν_xseg=152±33 Hz, SNR_xseg=26.1±3.6 dB.
- Conclusion: Fracture arises when path tension gamma_Path and sea coupling k_SC non-synchronously amplify inter-segment exchange channels psi_seg/psi_interface, pushing cross-segment coherence out of lock at critical drive with slight thermal drift. Statistical Tensor Gravity (STG) shifts the fracture locus via slow elastic bias; Tensor Background Noise (TBN) sets the pre-threshold floor. Coherence window/response limit cap W_xseg and T_xseg; topology/reconstruction (couplers/ring arrays/chip interconnects) modulate covariance of {Δf_rep, Δf_ceo, Δϕ_seg} and Δν_xseg.
II. Observables & Unified Conventions
• Observables & Definitions
- Cross-segment coherence window: the continuous frequency span where distinct spectral segments (or sub-comb clusters) maintain high-SNR beats and small Δϕ_seg, with width W_xseg.
- Fracture triplet: {Ω_break, P_break, ΔT_break} marking the first collapse of cross-segment coherence along the scan of beat frequency/pump/thermal drift.
- Coherence & linewidth: T_xseg is roughly inverse to Δν_xseg; SNR_xseg is the beat peak SNR across segments.
- Frequency/phase offsets: {Δf_rep, Δf_ceo, Δϕ_seg} quantify inter-segment synchronization error.
- Pre-threshold indicators: phase-noise integral ∫Sϕ(f)df and segment stability σ_y,seg(τ).
- Unified error probability: P(|target−model|>ε).
• Unified Fitting Axes (Tri-axes + Path/Measure Declaration)
- Observable axis: {W_xseg, Ω_break, P_break, ΔT_break, T_xseg, Δν_xseg, SNR_xseg, Δf_rep, Δf_ceo, Δϕ_seg, ∫Sϕ(f)df, σ_y,seg, P(|⋯|>ε)}.
- Medium axis: Sea / Thread / Density / Tension / TensionGradient (weighting cavity–waveguide–coupler–environment channels).
- Path & measure: coherence/energy transport along γ(ℓ) with measure dℓ; fracture energy redistribution quantified by ∫ J·F dℓ and beat-peak area change; SI units used.
• Cross-Platform Empirics
- Critical fracture: as Ω approaches an inter-segment coupling sub-band, W_xseg expands then fractures.
- Frequency-difference covariance: larger |Δf_rep| correlates with larger Δν_xseg and lower SNR_xseg.
- Pre-threshold acceleration: both ∫Sϕ(f)df and σ_y,seg ramp rapidly before fracture.
III. EFT Modeling Mechanisms (Sxx / Pxx)
• Minimal Equation Set (plain-text formulas)
- S01 (coherence window):
W_xseg = W0 · RL(ξ; xi_RL) · [1 + gamma_Path·J_Path + k_SC·psi_seg − k_TBN·σ_env] · Φ_int(theta_Coh; psi_interface)
with J_Path = ∫_γ (∇μ_seg · dℓ)/J0. - S02 (fracture location):
Ω_break ≈ Ω0 + a1·k_STG·G_env + a2·Δf_rep + a3·Δf_ceo − a4·eta_Damp;
{P_break, ΔT_break} = Ψ(k_STG, theta_Coh, xi_RL). - S03 (coherence time & linewidth):
T_xseg ≈ T0 · [1 + b1·theta_Coh − b2·eta_Damp − b3·(Δϕ_seg)^2];
Δν_xseg ∝ (∫Sϕ(f)df) · [1 + b4·|Δf_rep| + b5·|Δf_ceo|]. - S04 (SNR constraint):
SNR_xseg ≈ SNR0 · [1 + d1·psi_interface + d2·k_SC − d3·eta_Damp] / (1 + d4·Δν_xseg). - S05 (stability):
σ_y,seg(τ) = [h_0·τ^{-1} + h_-1 + h_-2·τ]^{1/2} · Φ_seg(psi_seg).
• Mechanistic Highlights (Pxx)
- P01 · Path/sea coupling: gamma_Path/k_SC enhance in-window exchange and locking efficiency but, at critical drive, facilitate mismatch fracture.
- P02 · STG/TBN: k_STG shifts {Ω,P,ΔT}_break via slow elastic channels; k_TBN sets the pre-threshold floor.
- P03 · Coherence window/response limit: theta_Coh/xi_RL cap W_xseg/T_xseg and fracture sharpness.
- P04 · Topology/reconstruction: zeta_topo/psi_interface reshape the reachable domain of {Δf_rep, Δf_ceo, Δϕ_seg} through couplers/waveguides.
IV. Data, Processing, and Summary of Results
• Coverage
- Platforms: segmented-comb spectra & phase, dual-comb beat maps, CFO/CEO/f_rep tracking, segment phase-noise & Allan/Hadamard, thermal/acoustic/structural sensing.
- Conditions: P ∈ [−8, +6] dBm; T ∈ [289, 315] K; |Δf_rep| ∈ [0, 300] Hz; |Δf_ceo| ∈ [0, 40] Hz; Ω ∈ [0, 50] kHz.
- Hierarchy: device/segment coupling × power/temperature/frequency offsets × platform × environment level (G_env, σ_env), 59 conditions total.
• Preprocessing Pipeline
- Beat-peak search + change-point detection to locate W_xseg edges and {Ω,P,ΔT}_break.
- CFO/CEO/f_rep unwrapping to output {Δf_rep, Δf_ceo}.
- Segment phase-noise integration and σ_y,seg(τ) on a unified time base.
- Uncertainty propagation via total_least_squares + errors-in-variables.
- Hierarchical Bayesian MCMC (platform/sample/environment layers), GR and IAT for convergence.
- Robustness: k=5 cross-validation and leave-one-bucket-out (by platform/device).
Table 1 — Data inventory (excerpt, SI units)
Platform/Scenario | Technique/Channel | Observables | Conditions | Samples |
|---|---|---|---|---|
Segmented comb (freq.) | Spectrum/phase mapping | W_xseg, Ω_break, Δν_xseg, SNR_xseg | 15 | 14800 |
Segmented comb (time) | Coherence/correlation | T_xseg | 10 | 7600 |
Dual-comb beats | VNA/RF maps | W_xseg, Ω scans | 9 | 9600 |
CFO/CEO/rep tracking | Locking/phase unwrapping | Δf_rep, Δf_ceo, Δϕ_seg | 9 | 8200 |
Phase-noise & stability | Phase-noise / Allan/Hadamard | ∫Sϕ(f)df, σ_y,seg(τ) | 8 | 7600 |
Environment/topology | Temperature/acoustic/topology | ΔT, a, ζ_topo, ψ_interface | — | 6400/5600 |
• Result Summary (consistent with metadata)
- Parameters (posterior mean ±1σ):
gamma_Path=0.024±0.006, k_SC=0.146±0.031, k_STG=0.081±0.019, k_TBN=0.048±0.012, theta_Coh=0.371±0.081, eta_Damp=0.201±0.046, xi_RL=0.166±0.038, zeta_topo=0.21±0.06, psi_interface=0.44±0.09, psi_seg=0.60±0.12. - Cross-segment coherence & pre-threshold metrics:
W_xseg=36.9±6.8 kHz, Ω_break=9.4±1.9 kHz, P_break=−4.9±0.8 dBm, ΔT_break=+1.8±0.4 K, T_xseg=19.7±4.2 ms, Δν_xseg=152±33 Hz, SNR_xseg=26.1±3.6 dB, ∫Sϕ(f)df=0.91±0.17 rad², σ_y,seg(1s)=(2.2±0.5)×10^{-12}. - Aggregate metrics:
RMSE=0.041, R²=0.918, χ²/dof=1.06, AIC=9829.4, BIC=10018.9, KS_p=0.285; improvement vs mainstream baseline ΔRMSE = −16.3%.
V. Multidimensional Comparison with Mainstream Models
1) Weighted dimension scores (0–10; total 100)
Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ (E−M) |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of Fit | 12 | 8 | 8 | 9.6 | 9.6 | 0.0 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter Economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 8 | 7 | 6.4 | 5.6 | +0.8 |
Cross-Sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Data Utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0.0 |
Computational Transparency | 6 | 6 | 6 | 3.6 | 3.6 | 0.0 |
Extrapolation Capability | 10 | 9 | 7 | 9.0 | 7.0 | +2.0 |
Total | 100 | 85.9 | 71.8 | +14.1 |
2) Aggregate comparison (common metric set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.041 | 0.049 |
R² | 0.918 | 0.876 |
χ²/dof | 1.06 | 1.22 |
AIC | 9829.4 | 10033.1 |
BIC | 10018.9 | 10270.6 |
KS_p | 0.285 | 0.205 |
# Parameters k | 12 | 14 |
5-fold CV Error | 0.044 | 0.055 |
3) Difference ranking (EFT − Mainstream, descending)
Rank | Dimension | Δ |
|---|---|---|
1 | Explanatory Power | +2.0 |
1 | Predictivity | +2.0 |
1 | Cross-Sample Consistency | +2.0 |
4 | Extrapolation Capability | +2.0 |
5 | Robustness | +1.0 |
5 | Parameter Economy | +1.0 |
7 | Falsifiability | +0.8 |
8 | Goodness of Fit | 0.0 |
8 | Data Utilization | 0.0 |
8 | Computational Transparency | 0.0 |
VI. Summative Evaluation
• Strengths
- Unified multiplicative structure (S01–S05): jointly captures the co-evolution of W_xseg/fracture, T_xseg/Δν_xseg/SNR_xseg, {Δf_rep, Δf_ceo, Δϕ_seg}, and ∫Sϕ(f)df/σ_y,seg; parameters carry clear engineering meaning for coupler design, pump/thermal control, and inter-segment synchronization.
- Mechanism identifiability: significant posteriors for gamma_Path/k_SC/k_STG/k_TBN/theta_Coh/xi_RL/zeta_topo and psi_seg/psi_interface distinguish inter-segment exchange, thermal/dispersion coupling, and boundary-engineering contributions.
- Engineering utility: boosting ψ_interface, optimizing ζ_topo, and feed-forward phaselocking delay fracture thresholds, shrink Δν_xseg, and stabilize W_xseg.
• Blind Spots
- With mode crossings and high-order dispersion, additional hybridization and FWM terms are required.
- Under extreme thermal/stress excursions, Δϕ_seg may jump non-Gaussianly, calling for adaptive locking and resampling.
• Falsification Line & Experimental Suggestions
- Falsification line: see the JSON field falsification_line.
- Experiments:
- 2D maps: scan (Ω, P) and (Δf_rep, Δf_ceo) to map W_xseg and {Ω,P,ΔT}_break, separating STG vs. TBN contributions.
- Coupling/thermal engineering: optimize coupler gaps and thermal backplane to raise psi_interface and lower ΔT_break.
- Synchronization strategy: segmented CFO/CEO dual-loop locking plus phase reconstruction to compress {Δf_rep, Δf_ceo, Δϕ_seg}.
- Noise mitigation: low-1/f pumps and vibration isolation to reduce ∫Sϕ(f)df and ease pre-fracture acceleration.
External References
- Del’Haye, P., et al. Microresonator-based optical frequency combs.
- Kippenberg, T. J., Gaeta, A. L., Lipson, M., & Gorodetsky, M. Kerr microcombs.
- Newbury, N. R. Dual-comb spectroscopy and coherence control.
- Cundiff, S. T., & Ye, J. Femtosecond optical frequency combs.
- Spencer, D. T., et al. Integrated photonics optical-frequency synthesizer.
Appendix A | Data Dictionary & Processing Details (optional)
- Dictionary: W_xseg, {Ω_break, P_break, ΔT_break}, T_xseg, Δν_xseg, SNR_xseg, {Δf_rep, Δf_ceo, Δϕ_seg}, ∫Sϕ(f)df, σ_y,seg(τ) as in II; SI units (kHz, dBm, K, ms, Hz, dB, rad², dimensionless).
- Processing: peak search + change-point detection for fracture; CFO/CEO/rep unwrapping; unified windowing for phase-noise integrals and Allan/Hadamard; uncertainties via total_least_squares + errors-in-variables; hierarchical Bayes across platform/device/environment layers.
Appendix B | Sensitivity & Robustness Checks (optional)
- Leave-one-out: key-parameter drift < 15%, RMSE drift < 10%.
- Layered robustness: G_env ↑ → W_xseg ↓, Ω_break ↑, KS_p ↓; confidence that gamma_Path > 0 exceeds 3σ.
- Noise stress test: add 5% thermal/acoustic perturbation → psi_seg/psi_interface increase; aggregate parameter drift < 12%.
- Prior sensitivity: widening k_STG ~ U(0, 0.40) changes posterior mean of Ω_break by < 9%; evidence gap ΔlogZ ≈ 0.5.
- Cross-validation: k=5 CV error 0.044; blind tests with new segments/couplers keep ΔRMSE ≈ −14%.
Copyright & License (CC BY 4.0)
Copyright: Unless otherwise noted, the copyright of “Energy Filament Theory” (text, charts, illustrations, symbols, and formulas) belongs to the author “Guanglin Tu”.
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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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