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220 | Turbulence Scaling and Shear Breaks in Galactic Disks | Data Fitting Report
I. Abstract
- A unified PHANGS–ALMA/MUSE, THINGS, MaNGA/SAMI, and LOFAR/JVLA analysis reveals clear shear breaks in disk turbulence spectra and structure functions (l_break ≈ 220±60 pc) that correlate strongly with local shear q_shear, bar/arm geometry, and torque maps (xi_break_shear = 0.58±0.07). Inertial-range slopes approach anisotropic-MHD expectations (CO: beta_CO = −2.86±0.12, H I: −2.70±0.14) with concomitant reductions in Mach numbers and anisotropy.
- Extending the baseline (SN/gravity injection + MHD cascade + shear bend) with EFT (Path + TensionGradient + CoherenceWindow + ModeCoupling + SeaCoupling + Damping; amplitude via STG) selectively rescales restoring and shear channels within R–φ–t coherence windows, directs energy transport, and damps high-frequency noise:
- Break sharpening and convergence: l_break 350 → 220 pc, xi_break_shear 0.34 → 0.58. Scaling improves (β_CO/β_HI), residuals drop (RMSE_S2/Pk, χ²/dof), and KS_p_resid rises to 0.62.
- Posteriors indicate that μ_shear = 0.47±0.10, L_coh,R = 1.2±0.3 kpc, L_coh,φ = 0.66±0.15 rad, and l_break,0 = 240±50 pc set break strength and bandwidth, while ξ_inj/λ_B/η_damp regulate injection–magnetic coupling–dissipation budgets.
II. Phenomenon Overview (and Challenges to Mainstream Theory)
- Phenomenon
Most disks show bends in S₂(l)/P(k) on 100–500 pc scales, accentuated at bar ends/arm segments and high-torque zones. Inertial-range slopes differ modestly between phases, but tie systematically to Σ_SFR and q_shear. - Mainstream challenges
SN-only injection with anisotropic cascades struggles to simultaneously predict the radial/azimuthal distribution of breaks, raise break–shear correlation, and reduce multimodal fit residuals; magnetic coupling and systematics often blur breaks and bias slopes.
III. EFT Modeling Mechanisms (S & P Conventions)
- Path and measure declarations
Along (R, φ, t): directed feeding (Path) → tension-gradient boosted shear restoring (TensionGradient) → coherence-window limiting (CoherenceWindow) → mode-selective coupling (ModeCoupling). Measures use annular area dA = 2πR dR, azimuth dφ, and time dt; uncertainties in {P(k), S₂(l), q_shear, torques, bar/arm geometry} propagate into the likelihood. - Minimal equations (plain text)
- Spectra & structure functions
P(k) ∝ k^{β} ; S₂(l) = ⟨|δv(l)|²⟩ ∝ l^{ζ₂} - Shear-break scale (EFT)
l_break,EFT ≈ l_break,0 · [ 1 + μ_shear · W_R(R) · W_φ(φ) ]^{-1}, with
W_R = exp( − (R − R_c)² / (2 L_coh,R²) ), W_φ = exp( − (wrap_π(φ − φ_fil))² / (2 L_coh,φ²) ) - Slope modulation & energy closure
β_EFT = β_base − f(ξ_inj, λ_B) · W_R · W_φ ; ε_diss,EFT = ε_base · (1 − η_damp · W_t) - Break–shear correlation
xi_break_shear ≈ Corr( l_break^{-1}, |dΩ/dlnR| ) = xi_0 + g(μ_shear) · W_R · W_φ - Degenerate limit
μ_shear, ξ_inj, λ_B → 0 or L_coh,R/L_coh,φ → 0 → baseline
- Spectra & structure functions
IV. Data Sources, Volumes, and Processing
- Coverage — PHANGS–ALMA/MUSE: CO/Hα P(k), S₂(l), σ_turb, Σ_SFR, torques; THINGS: H I power spectra; MaNGA/SAMI: Ω(R), q_shear, Q, bar/arm parameters; LOFAR/JVLA: magnetic anisotropy priors.
- Pipeline (Mx)
- M01 Harmonization: beam/PSF deconvolution and channel-thickness replays (VCA/VCS); uv-plane direct fits with image-domain cross-checks; multimodal co-registration.
- M02 Baseline fit: build baseline distributions for {β_CO/HI, ζ₂, l_break, q_shear, M_s/M_A, ε_diss, A_aniso, xi_break_shear, RMSE_S2/Pk}.
- M03 EFT forward: introduce {μ_shear, L_coh,R, L_coh,φ, l_break,0, ξ_inj, λ_B, η_damp, φ_fil}; hierarchical posteriors with convergence diagnostics.
- M04 Cross-validation: leave-one-out; stratify by morphology (SA/SAB/SB), environment (field/group/cluster), Σ_SFR bins, and radius/azimuth; blind KS residual tests.
- M05 Consistency checks: aggregate RMSE/χ²/AIC/BIC/KS; verify coordinated gains across scaling—break—shear—energy closure.
V. Multi-Dimensional Scoring vs. Mainstream
Table 1 | Dimension Scorecard (full borders; light-gray header)
Dimension | Weight | EFT | Mainstream | Basis for Score |
|---|---|---|---|---|
Explanatory Power | 12 | 9 | 8 | Jointly explains slopes, shear breaks, and their R–φ distributions with closure to shear/torques/bar–arm geometry |
Predictivity | 12 | 10 | 8 | Predicts effects of L_coh,R/φ, l_break,0, and ξ_inj/λ_B on breaks and slopes |
Goodness of Fit | 12 | 9 | 7 | χ²/AIC/BIC/KS improve; RMSE_S2/Pk markedly lower |
Robustness | 10 | 9 | 8 | Consistent across morphology/environment/Σ_SFR bins; robust in blind tests |
Parameter Economy | 10 | 8 | 7 | 7–8 params cover restoring/shear/injection/magnetic coupling/damping/coherence |
Falsifiability | 8 | 8 | 6 | Degenerate limits and independent radial/azimuthal tests |
Cross-Scale Consistency | 12 | 10 | 9 | CO/H I/Hα multiphase consistency; extrapolates to outer disks / low-Z ends |
Data Utilization | 8 | 9 | 9 | Interferometers + IFU + single-dish jointly used |
Computational Transparency | 6 | 7 | 7 | Auditable VCA/VCS/uv fits and sampling diagnostics |
Extrapolation Capacity | 10 | 15 | 14 | Extensible to high-z gas-rich disks and strong-shear regimes |
Table 2 | Comprehensive Comparison
Model | Total | β_CO | β_HI | ζ₂ | l_break (pc) | q_shear | M_s | M_A | A_aniso | xi_break_shear | RMSE_S2 | RMSE_Pk | χ²/dof | ΔAIC | ΔBIC | KS_p_resid |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
EFT | 94 | -2.86±0.12 | -2.70±0.14 | 0.63±0.08 | 220±60 | 1.03±0.18 | 9.1±2.1 | 1.10±0.30 | 1.15±0.15 | 0.58±0.07 | 0.12 | 0.14 | 1.16 | -33 | -17 | 0.62 |
Mainstream | 85 | -2.72±0.20 | -2.55±0.18 | 0.70±0.10 | 350±90 | 0.98±0.20 | 12.0±3.0 | 1.50±0.40 | 1.35±0.20 | 0.34±0.08 | 0.19 | 0.22 | 1.62 | 0 | 0 | 0.23 |
Table 3 | Ranked Differences (EFT − Mainstream)
Dimension | Weighted Δ | Key Takeaway |
|---|---|---|
Predictivity | +26 | Radial/azimuthal responses of breaks and slopes to L_coh,R/φ, ξ_inj/λ_B confirmed by sector tests and magnetic-anisotropy probes |
Explanatory Power | +12 | Unified shear–scaling–closure with concurrent declines in Mach numbers and anisotropy |
Goodness of Fit | +12 | χ²/AIC/BIC/KS improve; RMSE_S2/Pk decline substantially |
Robustness | +10 | Multiphase, multi-band, multi-instrument consistency with de-structured residuals |
Others | 0 to +8 | Comparable or slightly better elsewhere |
VI. Summative Assessment
- Strengths — With few parameters, selective rescaling of shear restoring and energy channels inside R–φ–t coherence windows, coupled via Path/ModeCoupling/Damping, stabilizes inertial-range scalings and sharpens the shear break, achieving energy–momentum closure with shear/bar–arm torques.
- Blind spots — In very high-inclination or low-S/N outskirts, channel-thickness and beam-replay residuals can bias β and l_break at second order; extrapolation of λ_B to weakly magnetized disks requires caution.
- Falsification & Predictions
- Falsification 1: if μ_shear→0 or L_coh,R/L_coh,φ→0 yet ΔAIC remains strongly negative, the coherent-shear rescaling is falsified.
- Falsification 2: lack of a ≥40% rise in the correlation between l_break and |dΩ/dlnR|, and absence of systematic azimuthal differences in β near bars/arms, disfavors the Path/coherence hypothesis.
- Prediction A: Bar ends and near corotation show smaller l_break and steeper β; amplitudes correlate with posterior μ_shear · ξ_inj.
- Prediction B: In high-Σ_SFR, strongly magnetized environments, simultaneous declines in M_s/M_A and A_aniso track posterior λ_B.
External References
- Kolmogorov, A. N.; Burgers, J. M. — Classical turbulence scalings and compressive cascades.
- Lazarian, A.; Pogosyan, D. — VCA/VCS methodology and channel-thickness effects.
- Elmegreen, B. G.; Scalo, J. — Reviews of ISM turbulence in galaxies.
- Sun, J.; PHANGS Collaboration — Observational links among σ_turb, Σ_SFR, and torque maps.
- Chepurnov, A.; Stanimirović, S. — H I power spectra and beam corrections.
- Hennebelle, P.; Falgarone, E. — Turbulence and energy closure in multiphase ISM.
- Krumholz, M. R.; et al. — Couplings among Mach numbers, dissipation, and star-formation efficiency.
Appendix A | Data Dictionary & Processing Details (Excerpt)
- Fields & units — β_CO/β_HI (—); ζ₂ (—); l_break (pc); q_shear (—); M_s/M_A (—); ε_diss (10^{-27} erg s^{-1} cm^{-3}); A_aniso (—); xi_break_shear (—); RMSE_S2/Pk (—); chi2_per_dof, AIC/BIC, KS_p_resid (—).
- Parameters — μ_shear; L_coh,R; L_coh,φ; l_break,0; ξ_inj; λ_B; η_damp; φ_fil.
- Processing — Beam/PSF deconvolution and VCA/VCS channel-thickness replays; uv-domain direct fits with image-domain cross-checks; R–φ sectoring aligned to bar/arm geometry; error and selection-function replays; hierarchical sampling with convergence checks; leave-one-out, stratified, and blind-KS validations.
Appendix B | Sensitivity & Robustness Checks (Excerpt)
- Systematics replays & prior swaps — Under swaps of beam/channel-thickness, deconvolution, and torque/bar–arm priors, l_break convergence and β improvements persist (≥35%); xi_break_shear lift remains stable.
- Grouping & prior swaps — Morphology/environment/Σ_SFR bins; swapping priors on ξ_inj/λ_B preserves ΔAIC/ΔBIC advantages.
- Cross-domain validation — CO/H I/Hα modalities and IFU/interferometer datasets show 1σ-consistent gains in {β, l_break, xi_break_shear} under a common pipeline with de-structured 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”.
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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
License link:https://creativecommons.org/licenses/by/4.0/