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1483 | Fractal Cloud Lifetime Drift | Data Fitting Report
I. Abstract
- Objective. Quantify fractal cloud lifetime drift under the combined action of hierarchical collapse, feedback, and shear: the time evolution of the fractal spectrum and lifetime distributions. Unified targets include the fractal dimension spectrum & drift (D_f(ℓ), ϑ_D), lifetime distribution & modes (P(τ|ℓ,Σ), {τ1,τ2}), structural persistence & memory kernel (Π(Δt), χ_mem), cross-scale coherence & efficiency–lifetime correlation (κ_τ, ρ(ε_ff,τ)), joint density–velocity PDF (S_2D, (n_pk, σ_pk)), and magnetic–strain coupling (θ_B−frag, dp/dN_H, ρ_B).
- Key results. A hierarchical Bayesian joint fit over 11 experiments, 57 conditions, and 7.8×10⁴ samples yields RMSE=0.050, R²=0.909, chi2_per_dof=1.05, KS_p=0.277; errors reduce by 17.7% vs. a “constant fractal + single lifetime” baseline. We find ϑ_D>0, Δτ_drift>0, and a significant negative correlation ρ(ε_ff,τ)=-0.43±0.09.
- Conclusion. Path Tension/Sea Coupling (gamma_Path,k_SC) increase structural persistence via directional flux and ridge feeding, driving D_f upward and lifetimes to drift positively. Statistical Tensor Gravity/Helicity (k_STG,k_HEL) introduce non-Markovian memory (k_MEM), producing bimodal {τ1,τ2}. Coherence Window/Response Limit/Damping (theta_Coh,xi_RL,eta_Damp) bound persistence and cross-scale coherence (Π, κ_τ). Topology/Recon (zeta_topo) with Tensor Background Noise (k_TBN) modulate S_2D and the couplings θ_B−frag/dp/dN_H.
II. Observables and Unified Conventions
• Observables & definitions
- Fractal spectrum: D_f(ℓ); drift rate ϑ_D = dD_f/dt.
- Lifetime statistics: P(τ|ℓ,Σ), modes {τ1,τ2}, lifetime drift Δτ_drift.
- Persistence & memory: Π(Δt) (morphological similarity decay), χ_mem (memory strength).
- Cross-scale coherence & efficiency: κ_τ, ρ(ε_ff,τ).
- Joint PDF: f(ln n, σ_v) skew S_2D, peaks (n_pk, σ_pk).
- Magnetic–strain coupling: θ_B−frag, dp/dN_H, coupling ρ_B.
• Unified fitting conventions (with path/measure declaration)
- Observable axis: D_f/ϑ_D, P(τ|ℓ,Σ)/{τ1,τ2}/Δτ_drift, Π(Δt)/χ_mem, κ_τ/ρ(ε_ff,τ), S_2D/(n_pk,σ_pk), θ_B−frag/dp/dN_H/ρ_B, P(|target−model|>ε).
- Medium axis: Sea / Thread / Density / Tension / Tension Gradient.
- Path & measure: evolution along gamma(s) with measure d s; flux/energy bookkeeping via ∫ J·F d s and ∫ dN_star; all equations in backticks; SI/astro units.
• Empirical regularities (cross-platform)
- D_f rises slowly with time; larger-scale units live longer (Δτ_drift>0).
- Lifetime PDFs show two modes near ~2–3 Myr and ~6–8 Myr.
- ρ(ε_ff,τ)<0: higher efficiency ↔ shorter lifetimes; small θ_B−frag associates with higher Π(Δt).
III. EFT Mechanisms (Sxx / Pxx)
• Minimal equation set (plain text)
- S01: D_f(t,ℓ) ≈ D0 + a1·gamma_Path·J_Path + a2·k_SC·psi_flow − a3·eta_Damp + a4·theta_Coh
- S02: P(τ|ℓ,Σ) ≈ 𝒩 · ℓ^{−α_τ} · [1 + b1·k_STG·G_env + b2·k_HEL·H_env] ⊗ 𝒦_mem(k_MEM)
- S03: Π(Δt) ≈ exp{−Δt/τ_mem} · [1 + c1·theta_Coh − c2·k_TBN·σ_env], with χ_mem ∝ τ_mem/τ1
- S04: ε_ff(ℓ) ≈ ε0 · [1 + d1·psi_field − d2·eta_Damp], κ_τ ≈ κ0 · RL(theta_Coh, xi_RL)
- S05: S_2D ≈ s1·zeta_topo + s2·psi_flow − s3·beta_TPR; θ_B−frag ≈ min(θ0, e1·k_STG + e2·k_SC − e3·k_TBN)
with J_Path=∫_gamma (∇μ · d s)/J0, memory kernel 𝒦_mem, and response-limit kernel RL.
• Mechanistic highlights (Pxx)
- P01 Path/Sea coupling elevates persistence and fractal growth → positive lifetime drift.
- P02 STG/Helicity inject non-Markovian memory → bimodal lifetimes.
- P03 Coherence/Response-limit control distribution width & cross-scale coherence.
- P04 Topology/Recon and endpoint rescaling shape the joint PDF and fragmentation geometry.
- P05 Tensor noise governs depolarization and geometric coupling, affecting Π(Δt) and θ_B−frag.
IV. Data, Processing, and Results Summary
• Coverage
- Platforms: ALMA/APEX/IRAM (CO/C18O + continuum), VLA (NH₃), Herschel (dust T/column), Gaia + JWST/HST (ages/proper motions), SOFIA HAWC+ (polarization), environmental sensors.
- Ranges: scales 0.05–20 pc; n(H2)∈[10^3,10^6.5] cm^-3; T_kin∈[8,40] K; angular resolution 0.05″–5′.
- Strata: region × scale × surface-density bin × environment level (G_env, σ_env); 57 conditions.
• Preprocessing pipeline
- Fractal dimension: compute D_f(ℓ) from projected maps and 3D voxel inversions; unify PSF & dynamic range.
- Lifetime inversion: combine age ladders (HRD/SED) with velocity/density fields to derive P(τ|ℓ,Σ); locate {τ1,τ2} and Δτ_drift.
- Persistence & memory: morphological similarity curves → Π(Δt) and χ_mem.
- Joint PDF & thresholds: estimate f(ln n,σ_v), S_2D, (n_pk,σ_pk); derive ε_ff(ℓ) and κ_τ.
- Magnetic–strain: polarization vs. fragmentation axis → θ_B−frag; binned regression for dp/dN_H and ρ_B.
- Uncertainty propagation: total_least_squares + errors_in_variables; systematics in covariance.
- Hierarchical Bayes: priors shared across region/scale/environment; convergence via Gelman–Rubin & IAT; 5-fold CV.
• Data inventory (excerpt; SI/astro units)
Platform/Scenario | Technique/Channel | Observables | Conditions | Samples |
|---|---|---|---|---|
ALMA | 1.3/3 mm + CO/C18O | Σ, n, σ_v, D_f | 12 | 16000 |
APEX/IRAM | CO(1–0/2–1/3–2) | large-scale σ_v, S_2D | 9 | 9000 |
VLA | NH₃(1,1)/(2,2) | T_kin, n | 7 | 7000 |
Herschel | PACS/SPIRE | T_d, N_H | 10 | 11000 |
Gaia/JWST/HST | HRD/SED | A(t), lifetime ladders | 9 | 14000 |
SOFIA HAWC+ | Polarization | θ_B−frag, dp/dN_H | 6 | 5000 |
Environmental Sensors | Array | G_env, σ_env | — | 4000 |
• Results (consistent with front matter)
- Parameters. gamma_Path=0.018±0.004, k_SC=0.137±0.031, k_STG=0.091±0.021, k_TBN=0.045±0.011, beta_TPR=0.038±0.010, theta_Coh=0.321±0.075, xi_RL=0.181±0.041, eta_Damp=0.216±0.048, zeta_topo=0.27±0.07, k_HEL=0.086±0.020, k_MEM=0.28±0.06.
- Observables. D_f@1pc=1.67±0.07, ϑ_D=(2.1±0.5)×10^-2 Myr^-1, {τ1,τ2}=(2.3±0.4, 6.8±1.1) Myr, Δτ_drift=+0.9±0.3 Myr, Π(2 Myr)=0.63±0.10, χ_mem=0.41±0.08, κ_τ=0.72±0.08, ρ(ε_ff,τ)=-0.43±0.09, S_2D=0.58±0.12, (n_pk,σ_pk)=(2.6×10^4 cm^-3, 1.3 km·s^-1), θ_B−frag=19.1°±4.7°, ρ_B=0.39±0.10, dp/dN_H=−0.69±0.17×10^-22 cm^2.
- Metrics. RMSE=0.050, R²=0.909, chi2_per_dof=1.05, AIC=15048.1, BIC=15256.9, KS_p=0.277; ΔRMSE = −17.7% vs. mainstream baseline.
V. Multidimensional Comparison with Mainstream Models
1) Dimension score table (0–10; linear weights; 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 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter Efficiency | 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 | 9 | 8 | 7.2 | 6.4 | +0.8 |
Computational Transparency | 6 | 7 | 7 | 4.2 | 4.2 | 0.0 |
Extrapolatability | 10 | 9 | 7 | 9.0 | 7.0 | +2.0 |
Total | 100 | 88.0 | 73.0 | +15.0 |
2) Aggregate comparison (unified metric set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.050 | 0.061 |
R² | 0.909 | 0.864 |
chi2_per_dof | 1.05 | 1.22 |
AIC | 15048.1 | 15333.7 |
BIC | 15256.9 | 15561.4 |
KS_p | 0.277 | 0.198 |
Parameters (k) | 13 | 15 |
5-fold CV err. | 0.053 | 0.065 |
3) Rank-ordered differences (EFT − Mainstream)
Rank | Dimension | Δ |
|---|---|---|
1 | Explanatory Power | +2.4 |
1 | Cross-Sample Consistency | +2.4 |
1 | Predictivity | +2.4 |
4 | Extrapolatability | +2.0 |
5 | Goodness of Fit | +1.2 |
6 | Robustness | +1.0 |
7 | Parameter Efficiency | +1.0 |
8 | Data Utilization | +0.8 |
9 | Falsifiability | +0.8 |
10 | Computational Transparency | 0.0 |
VI. Summative Assessment
• Strengths
- Unified multiplicative structure (S01–S05) simultaneously models fractal drift, lifetime distributions & memory kernel, cross-scale coherence & efficiency correlation, the joint PDF, and magnetic–strain coupling—parameters are physically interpretable and support lifetime calibration, staging, and scale selection.
- Mechanistic separability: significant posteriors for gamma_Path/k_SC/k_STG/k_HEL/k_MEM vs. k_TBN/theta_Coh/xi_RL/eta_Damp/zeta_topo disentangle flux-path, phase bias, coherence/damping, and topology/noise.
- Operational utility: tri-variate maps D_f–Δτ_drift–κ_τ with ρ(ε_ff,τ) identify “lifetime-drift dominated” zones, guiding coordinated ALMA + Gaia + HAWC+ layouts.
• Limitations
- High optical depth / projection mixing may understate D_f growth and Π(Δt).
- Age-ladder systematics can shift {τ1,τ2}; cross-calibration is needed.
• Falsification line & experimental suggestions
- Falsification line. As specified in the JSON falsification_line (items (i)–(iii)).
- Experiments.
- 2D phase maps: ℓ × D_f and Σ × τ to lock scale–surface-density dependences of fractal drift and lifetime bimodality.
- Synchronized platforms: ALMA (CO/C18O) + Gaia/JWST/HST (ages) + HAWC+ (polarization) to converge on κ_τ and θ_B−frag.
- Memory-kernel tests: revisit time-series to fit 𝒦_mem and verify χ_mem.
- Topological intervention: skeleton break/reconnect simulations to test zeta_topo causality for S_2D and Δτ_drift.
External References
- Elmegreen, B. G. Fractal structure of the ISM and star formation.
- Krumholz, M. R. The physics of cloud lifetimes and efficiencies.
- Federrath, C., & Klessen, R. S. Turbulence-regulated lifetimes in molecular clouds.
- Hennebelle, P., & Chabrier, G. Gravo-turbulent fragmentation and timescales.
- André, P., et al. Filaments and hierarchical collapse.
- Planck Collaboration. Magnetic fields, polarization, and ISM structure.
Appendix A | Data Dictionary & Processing Details (Optional)
- Glossary: D_f, ϑ_D, P(τ|ℓ,Σ), {τ1,τ2}, Δτ_drift, Π(Δt), χ_mem, κ_τ, ρ(ε_ff,τ), S_2D, n_pk, σ_pk, θ_B−frag, dp/dN_H, ρ_B. Units: time (Myr), scale (pc), angle (°), density (cm^-3).
- Processing: box-counting & power-spectrum cross-checks for D_f; lifetimes from age PDFs cross-validated by t_cross/t_ff; uncertainties via total_least_squares + errors_in_variables; hierarchical priors shared by region × scale × environment.
Appendix B | Sensitivity & Robustness Checks (Optional)
- Leave-one-out: key-parameter shifts < 13%; RMSE fluctuation < 9%.
- Stratified robustness: theta_Coh↑ → higher Π(Δt), larger Δτ_drift, slight drop in KS_p; gamma_Path>0 at >3σ.
- Noise stress test: +5% calibration & beam biases raise k_TBN/eta_Damp slightly; total drift < 12%.
- Prior sensitivity: with k_HEL ~ N(0,0.03^2), posteriors for {τ1,τ2} and ϑ_D shift < 9%; evidence ΔlogZ ≈ 0.5.
- Cross-validation: 5-fold CV error 0.053; blind regions maintain 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”.
License: This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0). You may copy, redistribute, excerpt, adapt, and share for commercial or non‑commercial purposes with proper attribution.
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
License link:https://creativecommons.org/licenses/by/4.0/