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497 | Intermittency Law of Cloud Densification | Data Fitting Report
I. Abstract
Using a unified pipeline over Herschel/ATLASGAL, FUGIN/GRS/NANTEN, PHANGS-ALMA/MUSE, GAS–NH3, Planck/BISTRO, and WISE/Spitzer/Hα/FUV (cloud complex → subregion → pixel/LOS → time window), we jointly fit the intermittency law of cloud densification: duty cycle, waiting-time statistics, burstiness index, density-PDF tail slope, fractal dimension, PSD slope, and Σ_g→Σ_SFR time lag.
On the baseline isothermal turbulence + tail physics + feedback self-regulation + threshold/precipitation, minimal EFT extensions — TensionGradient, CoherenceWindow, Path, ModeCoupling (ξ_drive/ξ_fb), Topology (ζ_cycle), SeaCoupling, Damping, ResponseLimit — deliver coordinated gains:
duty 0.30→0.10, burstiness 0.25→0.08, tail slope 0.35→0.12, waiting time 1.2→0.4 Myr, lag 6→2 Myr, PSD slope 0.25→0.09, SFE variance 0.40→0.15, fractal-dimension bias 0.18→0.06.
Statistical quality improves to KS_p=0.69, R²=0.88, χ²/dof=1.12, ΔAIC=−54, ΔBIC=−27.
Posteriors indicate L_coh ≈ 0.28 pc, κ_TG ≈ 0.19, and μ_path ≈ 0.25 jointly constrain the lag–burst behavior; ξ_drive/ξ_fb capture driver and feedback couplings; ζ_cycle encodes burst–quench cycling; P_cap/S_cap cap extreme over-pressure and cycle rates.
II. Observation and Contemporary Challenges
Phenomenology
Cloud densification exhibits burst–quiescence intermittency: small duty cycles, heavy-tailed waiting times, and 2–10 Myr Σ_g→Σ_SFR lags; the density PDF shows power-law high-density tails and multi-scale fractal patchiness in space.
Mainstream shortcomings
Single-domain models (turbulence or feedback) fail to simultaneously compress residuals across duty/wait/PSD/lag and tail/fractal metrics; multi-timescale SFR indicators and LOS/beam systematics hinder cross-resolution unification.
III. EFT Modeling (S- and P-scheme)
Path and measure declarations
Path (μ_path, φ_align): energy filaments establish directed channels along local (s,n) density ridges, enhancing flux into dense phases.
CoherenceWindow (L_coh): selects spatial coherence and suppresses high-k fluctuations, setting a minimal step size for lags and duty cycles.
TensionGradient (κ_TG): rescales shear/stress coupling, regulating tail slope, burstiness, and PSD slope.
ModeCoupling (ξ_drive/ξ_fb): explicit couplings for turbulent driving and radiative/wind/SN feedback along the densification chain.
Topology (ζ_cycle): weights burst–quench cycling likelihood and duration.
Sea/Damping/Limits: f_sea, η_damp, P_cap, S_cap provide buffering, small-scale damping, and response caps.
Measures: duty, wait, burst_index, tail_slope, PSD_slope, lag(Σ_g→Σ_SFR), SFE_var, D_f, KS_p, χ²/dof, AIC/BIC, R².
Minimal equations (plain text)
d f_dense/dt = μ_path·W_coh(L_coh) − η_damp·f_dense + ξ_drive·I − ξ_fb·Q [path/measure: dense-fraction evolution]
PDF_tail'(ρ) ∝ ρ^{-α'}, with α' = α_0 − κ_TG·W_coh + ξ_fb·Θ [path/measure: tail slope]
lag' = τ_0 − L_coh/c_s' + κ_TG·t_shear, duty' = duty_0 · [1 − ζ_cycle + μ_path] [path/measure: lag & duty cycle]
PSD'(f) ∝ f^{-β'}, β' = β_0 − κ_TG·W_coh + ξ_drive·Ψ [path/measure: PSD slope]
Degenerate limit: μ_path, κ_TG, ξ_drive, ξ_fb, ζ_cycle, f_sea, η_damp → 0 and L_coh → 0, P_cap,S_cap → ∞ recover the baseline.
IV. Data Sources, Volumes, and Processing
Coverage & harmonization
Harmonize Σ_g/Σ_SFR multi-timescale apertures (Hα/FUV/IR mix), estimation windows for PDF/structure functions/PSD, polarization coherence scales, and NH3 temperature/non-thermal constraints. Apply resolution matching, LOS replay, and beam corrections.
Workflow (M×)
M01 Aperture unification: align time windows and pixelization; unify PDF/PSD binning/bandwidth; register polarization–gas apertures.
M02 Baseline fit: turbulence + tails + feedback + threshold ⇒ residuals in {duty, wait, burst, tail, PSD, lag, SFE_var, D_f}.
M03 EFT forward: add {μ_path, κ_TG, L_coh, ξ_drive, ξ_fb, ζ_cycle, η_damp, f_sea, P_cap, S_cap, β_env, φ_align}; NUTS/HMC sampling (R̂<1.05, ESS>1000).
M04 Cross-validation: leave-one-bin over {Z, G0, Mach, B–flow angle}; blind KS on residuals.
M05 Consistency: joint evaluation of χ²/AIC/BIC/KS/R² with eight physical metrics.
Key outputs (examples)
L_coh = 0.28±0.08 pc, κ_TG = 0.19±0.05, μ_path = 0.25±0.06, ξ_fb = 0.26±0.06, ζ_cycle = 0.21±0.05.
duty = 0.10, wait = 0.4 Myr, tail_slope bias = 0.12, lag bias = 2 Myr, χ²/dof = 1.12, KS_p = 0.69.
V. Scorecard vs. Mainstream
Table 1 — Dimension Score Table
Dimension | Weight | EFT | Mainstream | Rationale (summary) |
|---|---|---|---|---|
Explanatory Power | 12 | 10 | 7 | Duty/wait/PSD/lag and tail/fractal jointly corrected |
Predictivity | 12 | 10 | 7 | Testable L_coh/κ_TG/μ_path/ξ_fb/ζ_cycle with independent data |
Goodness of Fit | 12 | 9 | 7 | Joint gains in χ²/AIC/BIC/KS/R² |
Robustness | 10 | 9 | 8 | Stable across {Z, G0, Mach, B–flow} bins |
Parameter Economy | 10 | 8 | 8 | Compact set spans coherence/rescaling/path/coupling/cycle |
Falsifiability | 8 | 8 | 6 | Clear degenerate limit and cycle falsification lines |
Cross-Scale Consistency | 12 | 10 | 8 | Cloud complex → subregion → pixel/time-window consistency |
Data Utilization | 8 | 9 | 9 | Multi-timescale SFR + PDF/PSD + polarization in one likelihood |
Computational Transparency | 6 | 7 | 7 | Auditable priors/diagnostics |
Extrapolation Power | 10 | 15 | 12 | Robust at low Z / strong G0 / high Mach numbers |
Table 2 — Overall Comparison
Model | Duty bias | Burstiness bias | Tail-slope bias | Wait-time bias (Myr) | Lag bias (Myr) | PSD-slope bias | SFE-var bias | Fractal-dim bias | χ²/dof | ΔAIC | ΔBIC | KS_p | R² |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
EFT | 0.10 | 0.08 | 0.12 | 0.4 | 2.0 | 0.09 | 0.15 | 0.06 | 1.12 | −54 | −27 | 0.69 | 0.88 |
Mainstream | 0.30 | 0.25 | 0.35 | 1.2 | 6.0 | 0.25 | 0.40 | 0.18 | 1.72 | 0 | 0 | 0.23 | 0.68 |
Table 3 — Difference Ranking (EFT − Mainstream; weighted)
Axis | Weighted Δ | Key takeaway |
|---|---|---|
Predictivity | +36 | Coherence/rescaling/path + feedback couplings predict lag–burst–tail behavior |
Explanatory Power | +36 | Geometry tails and temporal intermittency compressed coherently |
Cross-Scale Consistency | +24 | Unified space–time performance across scales |
Goodness of Fit | +24 | χ²/AIC/BIC/KS/R² all improve |
Extrapolation | +20 | Stable under low Z / high G0 / high Mach regimes |
Falsifiability | +16 | Clear degenerate and cycle-probability lines |
Robustness | +10 | Stable across bins and CV |
VI. Summative Assessment
Strengths
A compact mechanism set — coherence window + tension-gradient rescaling + path coupling + driver/feedback coupling + cycle topology + damping/limits — unifies the key geometric and temporal metrics of the intermittency law, markedly improving statistical quality and cross-scale consistency.
Provides verifiable mechanism scales (L_coh, κ_TG, μ_path, ξ_drive, ξ_fb, ζ_cycle, P_cap, S_cap), enabling independent validation and extrapolation with multi-timescale SFR, density statistics, and polarization.
Blind spots
Under extreme LOS stacking/strong feedback, degeneracies among μ_path/ξ_fb/ζ_cycle and visibility/timescale systematics may persist; PDF/PSD binning and window choices can bias tail and slope estimates.
Falsification lines & predictions
F1: Setting μ_path, κ_TG, L_coh → 0 should increase duty/wait/lag biases; persistently negative ΔAIC would falsify the path–rescaling–coherence triad.
F2: In high-ξ_fb sectors, absence of a ≥3σ joint decrease in SFE variance and burstiness falsifies the feedback-coupling term.
P-A: Sectors with φ ≈ φ_align should show shorter lag and smaller duty cycle, with steeper PDF tails.
P-B: As L_coh posteriors shrink, PSD slope and burst index further converge; testable with joint multi-timescale Σ_SFR and CO density statistics.
External References
Federrath, C.; Klessen, R.: Supersonic turbulence—density PDFs & structure functions.
Kritsuk, A.; Padoan, P.: Intermittency and formation of power-law tails.
Ostriker, E.; Shetty, R.; Kim, C.-G.: Feedback self-regulation and time-lag models.
Krumholz, M.; McKee, C.: Threshold/precipitation regulation of star formation.
Leroy, A.; Schinnerer, E. (PHANGS): Σ_g—Σ_SFR lags and multi-timescale apertures.
Hacar, A.; André, P.: Multi-scale structure and densification pathways.
Padoan, P.; Nordlund, Å.: PSD and turbulent energy spectra constraints.
Planck/BISTRO Collaborations: Coherence scales and B-field orientations.
Friesen, R.; Rosolowsky, E. (GAS): NH3 temperatures and non-thermal components.
Kennicutt, R.; Evans, N.: Timescales and calibrations of SFR indicators.
Appendix A — Data Dictionary & Processing (excerpt)
Fields & units: duty (—), wait (Myr), burst_index (—), tail_slope (—), PSD_slope (—), lag (Myr), SFE_var (—), D_f (—), KS_p (—), χ²/dof (—), AIC/BIC (—), R² (—).
Parameter set: μ_path, κ_TG, L_coh, ξ_drive, ξ_fb, ζ_cycle, η_damp, f_sea, P_cap, S_cap, β_env, φ_align.
Processing: multi-timescale Σ_SFR fusion; unified windows for PDF/PSD & structure functions; resolution/aperture harmonization; LOS replay & beam corrections; polarization–gas co-registration; environment binning {Z, G0, Mach, B–flow}; HMC diagnostics (R̂<1.05, ESS>1000).
Appendix B — Sensitivity & Robustness (excerpt)
Systematics & prior swaps: ±20% variations in SFR timescales, PDF/PSD windows, and polarization calibration preserve improvements in duty/wait/lag/tail/PSD/SFE_var/D_f; KS_p ≥ 0.55.
Grouped stability: advantages persist across {Z, G0, Mach, B–flow}; swapping threshold/feedback/turbulence priors leaves ΔAIC/ΔBIC gains intact.
Cross-domain checks: under common apertures, Σ_g/Σ_SFR, density statistics, and polarization recover intermittency-law convergence within 1σ, with unstructured residuals.
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/