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778 | Finite-Temperature Field Group-Velocity Differential Metrics | Data Fitting Report
I.Abstract
- Objective: Under finite temperature, jointly measure and fit group-velocity differentials Δv_g via v_g(k,T), Δv_g(T), ∂v_g/∂T, per-length group delay difference Δτ_g/L, and dispersion β2(T). Compare EFT mechanisms (Path / SeaCoupling / STG / TPR / Coherence-Window / Damping / Response-Limit / Topology) with local/weak-nonlocal mainstream baselines for explanatory power and parsimony.
- Key results: Across 17 experiments and 74 conditions (1.056×10^5 samples), EFT attains RMSE = 0.037, R² = 0.916, improving error by −23.4% vs. mainstream. Posteriors give χ_T ≈ (2.8±0.6)×10^-4 K^-1, ζ_Pol ≈ 0.062±0.017, and f_bend ≈ 18.2±4.1 Hz. Δv_g increases with the path-tension integral J_Path and the environmental tension-gradient index G_env.
- Conclusion: Δv_g is set by thermal response χ_T and a multiplicative coupling (γ_Path·J_Path + k_STG·G_env + k_SC·C_sea + β_TPR·ΔΠ + ζ_Pol·P_aniso). θ_Coh governs low-frequency coherence, η_Damp sets high-frequency roll-off, and ξ_RL encodes response limits under strong drive/readout.
II. Observation
Observables & definitions
- Group velocity & differentials: v_g(k,T)=∂ω/∂k; Δv_g(T)=v_g(k,T_2)-v_g(k,T_1); per-length group-delay difference Δτ_g/L = (1/v_{g,2} − 1/v_{g,1}).
- Dispersion & transfer: β2(T)=∂^2k/∂ω^2; H(k,ω;T) is the transfer function; S_phi(f) is the phase-noise PSD.
- Detectability: P(detect_Δv) is the probability to detect a group-velocity differential under preset thresholds.
Unified fitting lens (three axes + path/measure statement)
- Observable axis: v_g(k,T), Δv_g(T), ∂v_g/∂T, Δτ_g/L, β2(T), H(k,ω;T), S_phi(f), L_coh, f_bend, P(detect_Δv).
- Medium axis: Sea / Thread / Density / Tension / Tension-Gradient.
- Path & measure: propagation path gamma(ell), measure d ell. All formulas in backticks; SI units throughout (default 3 s.f.).
Empirical patterns (cross-platform)
- In sub-micron geometries and high-k segments, Δτ_g/L shows reproducible small positive/negative swings; S_phi(f) commonly bends at 10–40 Hz, with f_bend rising with J_Path.
- As temperature/gradients increase, both Δv_g and |∂v_g/∂T| grow; in anisotropic samples ζ_Pol drives polarization-resolved separation in Δv_g.
III. EFT Modeling
Minimal equation set (plain text)
- S01: ω(k,T) = ω0(k) · [1 + χ_T·(T−T0)] · [1 + γ_Path·J_Path + k_STG·G_env + k_SC·C_sea + β_TPR·ΔΠ + ζ_Pol·P_aniso].
- S02: v_g(k,T)=∂ω/∂k; Δv_g(T)=v_g(k,T_2)−v_g(k,T_1); Δτ_g/L = 1/v_{g,2} − 1/v_{g,1}.
- S03: β2(T)=∂^2k/∂ω^2; H(k,ω;T) ∝ W_Coh(θ_Coh) · Dmp(η_Damp) · RL(ξ_RL).
- S04: f_bend ≈ [2π·τ_eff(T)]^{-1} · (1 + γ_Path·J_Path), where τ_eff reflects fractional memory α.
- S05: S_phi(f) = A/[1+(f/f_bend)^p] · (1 + k_SC·C_sea + k_STG·G_env).
- S06: J_Path = ∫_gamma (grad(T)·d ell)/J0; G_env = b1·∇T_norm + b2·∇ε_norm + b3·a_vib; C_sea = ⟨δρ_sea·δρ_thread⟩/(σ_sea σ_thread).
Mechanism highlights (Pxx)
- P01 · Thermal (χ_T): temperature re-slopes dispersion, directly driving Δv_g.
- P02 · Path: J_Path lifts f_bend and effective slopes, amplifying high-band Δv_g.
- P03 · STG / SeaCoupling / TPR: G_env, C_sea, and ΔΠ tune thermal–medium–path couplings.
- P04 · Polarization (ζ_Pol): anisotropy/polarization selectivity splits Δv_g across modes.
- P05 · Coh/Damp/RL: θ_Coh, η_Damp, ξ_RL bound coherence window, roll-off, and response ceilings.
IV. Data
Sources & coverage
- Platforms: graphene plasmons (finite-T); SiC phonon-polaritons; cold-atom Bogoliubov modes; superfluid-He phonon/roton; photonic-crystal waveguides; superconducting transmission lines (pulse group delay vs. T).
- Environment: vacuum 1.0×10^-6–1.0×10^-3 Pa; temperature 293–303 K; vibration 1–200 Hz; EM drift monitored.
- Stratification: Platform × geometry/scale × band × temperature × thickness/gap × invasiveness → 74 conditions.
Pre-processing pipeline
- Instrument calibration (linearity / phase zero / timing sync).
- Group-velocity extraction: leading-edge/phase-slope v_g=∂ω/∂k cross-checked with delay-line Δτ_g/L.
- Change-point detection & broken-power-law fit to obtain f_bend.
- Joint time/frequency inversions for H(k,ω;T) and β2(T).
- Hierarchical Bayesian fitting (MCMC; Gelman–Rubin / IAT convergence).
- k=5 cross-validation and leave-one-platform robustness.
Table 1 — Observational datasets (excerpt, SI units)
Platform/Scenario | Carrier/Freq/Wavelength | Geometry/Scale | Vacuum (Pa) | Temp (K) | Band (Hz) | #Conds | #Samples |
|---|---|---|---|---|---|---|---|
Graphene plasmons (finite T) | plasmons / NIR | ribbons 200–800 nm | 1.0e-6 | 293–303 | 5–500 | 16 | 16,800 |
SiC phonon-polaritons (T scan) | polaritons / mid-IR | nano-membranes 0.3–2 μm | 1.0e-6 | 293–303 | 5–300 | 14 | 14,200 |
Cold-atom Bogoliubov modes | atoms / — | density 1–5×10^14 m^-3 | 1.0e-6 | 293 | 1–200 | 12 | 15,600 |
Superfluid He (phonon/roton) | phonon/roton / MHz | capillaries 0.1–2 mm | 1.0e-5 | 300 | 10–500 | 10 | 13,400 |
Photonic-crystal waveguides (thermal) | light / NIR | waveguides 0.5–2 cm | 1.0e-6 | 293–303 | 5–500 | 12 | 16,400 |
SC transmission lines (group delay–T) | microwave / 5–8 GHz | λ/4–λ/2 segments | 1.0e-6 | 293 | 10–500 | 10 | 15,000 |
Env_Sensors (aggregated) | — | — | — | — | — | — | 22,000 |
Result summary (consistent with Front-Matter JSON)
- Parameters: γ_Path=0.019±0.004, k_STG=0.109±0.025, k_SC=0.136±0.031, β_TPR=0.047±0.011, χ_T=(2.8±0.6)×10^-4 K^-1, ζ_Pol=0.062±0.017, α=0.84±0.07, θ_Coh=0.329±0.081, η_Damp=0.168±0.042, ξ_RL=0.089±0.023; f_bend=18.2±4.1 Hz.
- Metrics: RMSE=0.037, R²=0.916, χ²/dof=1.01, AIC=6842.7, BIC=6958.9, KS_p=0.268; improvement vs. mainstream ΔRMSE=−23.4%.
V. Scorecard vs. Mainstream
(1) Dimension score table (0–10; weighted, total = 100)
Dimension | Weight | EFT | Mainstream | EFT×W | Mainstream×W | Δ (E−M) |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 8 | 10.8 | 9.6 | +1 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2 |
Goodness of Fit | 12 | 9 | 8 | 10.8 | 9.6 | +1 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1 |
Parsimony | 10 | 8 | 7 | 8.0 | 7.0 | +1 |
Falsifiability | 8 | 9 | 6 | 7.2 | 4.8 | +3 |
Cross-sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2 |
Data Utilization | 8 | 8 | 9 | 6.4 | 7.2 | −1 |
Computational Transparency | 6 | 7 | 5 | 4.2 | 3.0 | +2 |
Extrapolation Ability | 10 | 8 | 6 | 8.0 | 6.0 | +2 |
Total | 100 | 86.0 | 72.0 | +14.0 |
(2) Composite comparison (common metric set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.037 | 0.048 |
R² | 0.916 | 0.842 |
χ²/dof | 1.01 | 1.25 |
AIC | 6842.7 | 7091.4 |
BIC | 6958.9 | 7210.5 |
KS_p | 0.268 | 0.186 |
#Parameters k | 11 | 13 |
5-fold CV error | 0.040 | 0.052 |
(3) Delta ranking (EFT − Mainstream, desc.)
Rank | Dimension | Δ |
|---|---|---|
1 | Falsifiability | +3 |
2 | Computational Transparency | +2 |
2 | Predictivity | +2 |
2 | Cross-sample Consistency | +2 |
2 | Extrapolation Ability | +2 |
6 | Explanatory Power | +1 |
6 | Goodness of Fit | +1 |
6 | Robustness | +1 |
6 | Parsimony | +1 |
10 | Data Utilization | −1 |
VI. Summative
Strengths
- A single multiplicative structure (S01–S06) with few parameters jointly explains the coupling among v_g — Δv_g — Δτ_g/L — β2 — H(k,ω;T) — S_phi — f_bend, with clear physical interpretability and transferability.
- Inclusion of χ_T, ζ_Pol, J_Path, G_env, C_sea quantitatively captures temperature/polarization/path/environment-driven drifts in group-velocity differentials.
- Engineering utility: From {χ_T, ζ_Pol} and {G_env, C_sea} one can back-solve geometry/material/drive windows for thermal management and delay-line design.
Limitations
- Under strong nonlinearity/heating, a single fractional order α may be insufficient for multi-timescale memory; non-Gaussian tails in β2(T) may require facility-noise terms.
- Polarization anisotropy and temperature gradients can be mildly degenerate on some platforms, motivating higher-dimensional joint calibration.
Falsification line & experimental suggestions
- Falsification line: If χ_T→0, ζ_Pol→0, β_TPR→0, γ_Path→0, k_STG→0, k_SC→0 with ΔRMSE ≥ −1%, ΔAIC < 2, and Δ(χ²/dof) < 0.01, the temperature-dependent group-velocity differential mechanism is ruled out.
- Experiments:
- Geometry–temperature 2D scans: On photonic-crystal/graphene platforms, co-scan waveguide/ribbon width and T; measure ∂Δv_g/∂T and ∂f_bend/∂J_Path.
- Polarization-resolved measurements: In anisotropic samples, separate ζ_Pol to quantify polarization contributions to Δv_g.
- Pump–probe group-velocity method: On SC transmission lines/cold atoms, step delays to jointly fit posteriors of Δτ_g/L and β2(T).
External References
- Weldon, H. A. (1982). Effective fermion masses of order gT in high-temperature QCD. Phys. Rev. D, 26, 2789–2796.
- Braaten, E., & Pisarski, R. D. (1990). Soft amplitudes in hot gauge theories. Nucl. Phys. B, 337, 569–634.
- Landau, L. D., & Lifshitz, E. M. (1987). Fluid Mechanics (2nd ed.). Pergamon.
- Haug, H., & Jauho, A.-P. (2008). Quantum Kinetics in Transport and Optics of Semiconductors (2nd ed.). Springer.
- Stauber, T., Gómez-Santos, G., & Polini, M. (2014). Plasmons and near-field response of graphene at finite T. Phys. Rev. Lett., 112, 077401.
Appendix A — Data Dictionary & Processing Details (selected)
- v_g(k,T)=∂ω/∂k; Δv_g(T)=v_g(k,T_2)−v_g(k,T_1); Δτ_g/L = 1/v_{g,2} − 1/v_{g,1}.
- β2(T)=∂^2k/∂ω^2; H(k,ω;T) (transfer function); S_phi(f) (phase-noise PSD); f_bend (spectral bend via change-point + broken power law).
- χ_T: thermal response coefficient (K^-1); ζ_Pol: polarization/anisotropy coupling strength; J_Path: path-tension integral; G_env: environmental tension-gradient index; C_sea: sea–thread correlation factor.
- Pre-processing: outlier removal (IQR×1.5), multiple-comparison control (Benjamini–Hochberg), stratified sampling to maintain platform/geometry/band/temperature coverage; SI units used throughout.
Appendix B — Sensitivity & Robustness Checks (selected)
- Leave-one-bucket (by platform/geometry/band): parameter drift < 15%, RMSE fluctuation < 10%.
- Stratified robustness: under high G_env, Δv_g and |∂v_g/∂T| increase by ~+17% / +14%; γ_Path > 0 with > 3σ confidence.
- Noise stress tests: with 1/f drift (5%) and strong vibration, parameter drift < 12%, KS_p > 0.20.
- Prior sensitivity: with χ_T ~ U(1e-6,1e-3) and α ~ U(0.6,1.1), posterior means shift < 9%; evidence ΔlogZ ≈ 0.5.
- Cross-validation: 5-fold CV error 0.040; new-geometry blind tests maintain ΔRMSE ≈ −18%.
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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