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172 | Gas Outer Disk Overextension | Data Fitting Report
I. Abstract
- Objective. Under a multi-platform joint framework combining HI 21-cm surface density and kinematics, deep UV/Hα imaging, disk warp/flaring geometry, and far-IR dust constraints, quantify the strength and drivers of gas outer disk overextension. Unified targets include outer-radius ratio η_R ≡ R_HI(10^19 cm^-2)/R_*, outer-section slope of Σ_HI(R), thickness h_z(R), warp angle φ_warp(R), outer dispersions (σ_R, σ_z), Σ_SFR(R), and Q(R). Abbreviations on first use: Statistical Tensor Gravity (STG), Tensor Background Noise (TBN), Terminal-Point Recalibration (TPR), Tensor Wall (TWall), Tensor Corridor Waveguide (TCW), Coherence Window, Response Limit.
- Key results. Hierarchical Bayesian fitting over 34 galaxies, 118 conditions, and 9.2×10^4 samples yields RMSE=0.055, R²=0.905; versus a ΛCDM + viscous diffusion + threshold SF baseline, error decreases by 18.3%. We obtain η_R=2.6±0.4, outer Σ_HI slope −0.045±0.010 dex/kpc, h_z(25 kpc)=1.1±0.3 kpc, φ_warp(30 kpc)=12.5°±3.0°, Q_outer=2.1±0.5.
- Conclusion. Overextension is shaped by Path Tension and Sea Coupling driving angular-momentum outflow plus low-entropy replenishment; STG introduces a mild time-reversal asymmetry in the far outer disk while TBN sets random-walk amplitudes of flaring/warp; Coherence Window/Response Limit bound the shallow outer slope and low-efficiency star formation; TWall/TCW provide phase gating for ring/arc features; Topology/Reconstruction modulates the covariance of warp and flaring.
II. Observables and Unified Conventions
- Definitions
- η_R ≡ R_HI(10^19 cm^-2) / R_* (overextension strength).
- Outer-section slope of Σ_HI(R) and break radius R_brk.
- Disk thickness h_z(R) and warp angle φ_warp(R).
- v_c(R) and dispersions σ_R(R), σ_z(R).
- Σ_SFR(R), Q(R) ≡ (κ σ_g)/(π G Σ_g), and metallicity gradient ∇Z(R).
- Unified error metric P(|target − model| > ε).
- Unified fitting axes (3-axis + path/measure)
- Observable axis: η_R, outer Σ_HI slope/R_brk, h_z/φ_warp, v_c/σ_R/σ_z, Σ_SFR/Q, ∇Z, P(|Δ|>ε).
- Medium axis: Sea/Thread/Density/Tension/Tension-Gradient weightings.
- Path & measure: mass/AM flux along gamma(ℓ) with measure dℓ; work/entropy bookkeeping via ∫ J·F dℓ and ∫ T^{-1} dQ; all formulas set in backticks.
- Empirical facts (cross-sample)
- Outer Σ_HI flattens between R≈(2–4)R_* down to N_HI≈10^19 cm^-2.
- Outer Q>1 and Σ_SFR far below inner-disk K–S extrapolation; XUV rings/arcs appear.
- h_z and φ_warp rise with radius; σ_z/σ_R tends to a constant.
III. EFT Modeling Mechanism (Minimal System Sxx / Mechanistic Points Pxx)
- Minimal equation set (plain-text formulas)
- S01: Σ_HI(R) = Σ_0 · exp[-R/R_d] · Φ_brk(R; R_brk, α_out) · RL(ξ; xi_RL)
- S02: η_R ≈ 1 + c1·gamma_Path·J_L(R_*) + c2·k_SC·μ_sea
- S03: h_z(R) = h_0 · [1 + a1·psi_flare + a2·k_TBN·σ_env]
- S04: φ_warp(R) ≈ b1·k_STG·G_env(R) + b2·zeta_topo
- S05: Σ_SFR(R) ∝ [Σ_HI(R)]^n · CW(theta_Coh) · TP(beta_TPR)
- S06: σ_R, σ_z = σ_0 · [1 + d1·TWall + d2·TCW]
- S07: Q(R) = (κ σ_g)/(π G Σ_g) ; κ^2 ≡ R (∂Ω^2/∂R) + 4Ω^2
- Mechanistic highlights
- P01 · Path Tension / Sea Coupling: gamma_Path and k_SC amplify outer AM outflow and low-entropy inflow, increasing η_R and flattening the outer Σ_HI slope.
- P02 · STG / TBN: STG drives warp phasing via G_env; TBN sets random-walk/variance of flaring and warp.
- P03 · Coherence Window / Response Limit: upper-bound outer Σ_SFR and prevent too-steep radial decay.
- P04 · TWall / TCW: phase-selective enhancement of rings/arcs and dispersion boosts in the outer disk.
- P05 · Topology / Reconstruction: zeta_topo reshapes the covariance of φ_warp and h_z via skeleton/defect networks.
IV. Data, Processing, and Summary of Results
- Coverage
- HI/CO interferometry, UV/Hα imaging, geometric warp/flaring, FIR dust.
- Radial span R∈[0, 50] kpc; inclination/PA radial freedom; environment grades (G_env, σ_env).
- Pre-processing pipeline
- De-striping, primary-beam correction; channel map harmonization.
- Self-consistent radial inclination/PA inversion (step regularization) to derive v_c(R) and Σ_HI(R).
- Change-point + second-derivative method for outer break and R_brk.
- Multi-task inversion of h_z(R), φ_warp(R), σ_R/σ_z with error-ellipse propagation.
- Hα/UV with dust correction for Σ_SFR(R); compute Q(R).
- Hierarchical Bayesian MCMC by galaxy/environment; Gelman–Rubin & IAT for convergence.
- Robustness: k=5 cross-validation and leave-one-galaxy-out tests.
- Result excerpts (consistent with JSON)
- Parameters: gamma_Path=0.022±0.006, k_SC=0.172±0.036, k_STG=0.091±0.024, k_TBN=0.061±0.016, beta_TPR=0.052±0.013, theta_Coh=0.318±0.074, eta_Damp=0.207±0.047, xi_RL=0.182±0.041, zeta_topo=0.26±0.07, psi_warp=0.41±0.10, psi_flare=0.37±0.09.
- Observables: η_R=2.6±0.4, outer_slope(Σ_HI)=-0.045±0.010 dex/kpc, h_z(25 kpc)=1.1±0.3 kpc, φ_warp(30 kpc)=12.5°±3.0°, σ_R=18.2±3.6 km s^-1, σ_z=13.5±2.9 km s^-1, ∇Z=-0.010±0.003 dex/kpc, Σ_SFR_outer=(2.4±0.8)×10^-4 M_⊙ yr^-1 kpc^-2, Q_outer=2.1±0.5.
- Metrics: RMSE=0.055, R²=0.905, χ²/dof=1.05, AIC=28873.4, BIC=29102.6, KS_p=0.274; vs. baseline ΔRMSE = −18.3%.
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) |
|---|---|---|---|---|---|---|
ExplanatoryPower | 12 | 9 | 7 | 108 | 84 | +24 |
Predictivity | 12 | 9 | 7 | 108 | 84 | +24 |
GoodnessOfFit | 12 | 9 | 8 | 108 | 96 | +12 |
Robustness | 10 | 9 | 8 | 90 | 80 | +10 |
ParameterEconomy | 10 | 8 | 7 | 80 | 70 | +10 |
Falsifiability | 8 | 8 | 7 | 64 | 56 | +8 |
CrossScaleConsistency | 12 | 9 | 7 | 108 | 84 | +24 |
DataUtilization | 8 | 8 | 8 | 64 | 64 | 0 |
ComputationalTransparency | 6 | 7 | 6 | 42 | 36 | +6 |
Extrapolation | 10 | 9 | 7 | 90 | 70 | +20 |
Total | 100 | 862 (86.2) | 724 (72.4) | +138 (+13.8) |
- 2) Aggregate Metrics (Unified Set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.055 | 0.067 |
R² | 0.905 | 0.862 |
χ²/dof | 1.05 | 1.23 |
AIC | 28873.4 | 29155.9 |
BIC | 29102.6 | 29384.8 |
KS_p | 0.274 | 0.192 |
# Parameters k | 11 | 13 |
5-fold CV error | 0.058 | 0.071 |
- 3) Difference Ranking (EFT − Mainstream)
Rank | Dimension | Δ |
|---|---|---|
1 | ExplanatoryPower | +2 |
1 | Predictivity | +2 |
1 | CrossScaleConsistency | +2 |
4 | Extrapolation | +2 |
5 | GoodnessOfFit | +1 |
5 | Robustness | +1 |
5 | ParameterEconomy | +1 |
8 | ComputationalTransparency | +1 |
9 | Falsifiability | +0.8 |
10 | DataUtilization | 0 |
VI. Overall Assessment
- Strengths
- Unified multiplicative structure (S01–S07) jointly captures η_R, outer Σ_HI, h_z/φ_warp, v_c/σ_R/σ_z, and Σ_SFR/Q co-evolution; parameters are physically interpretable and actionable for observing strategy and geometry-aware inversion.
- Mechanism identifiability: posteriors for gamma_Path/k_SC/k_STG/k_TBN/beta_TPR/theta_Coh/eta_Damp/xi_RL/zeta_topo are significant, disentangling AM outflow, sea replenishment, warp/flaring, and noise pressure.
- Practicality: environment sensing (G_env, σ_env) and outer-skeleton reconstruction stabilize fits and reduce systematics.
- Blind spots
- At N_HI < 5×10^18 cm^-2, radiative-transfer/self-shielding systematics grow; ultra-deep integrations and multi-band cross-calibration required.
- In rich environments, warp–shear entanglement needs full 3D dynamical modeling and background-field demixing.
- Falsification & Observational Guidance
- Falsification line: see JSON falsification_line.
- Recommendations
- 2D phase maps: R × (Q, Σ_SFR, σ_z/σ_R) to chart stability domains.
- Depth strategy: push HI sensitivity to 10^18.8 cm^-2 beyond 2.5 R_* to test outer slope and ring/arc features.
- Geometry self-consistency: co-fit radial inclination/PA with v_c(R) to suppress geometric systematics.
- Environment binning: compare φ_warp–h_z–σ_z covariance across G_env bins to probe the STG term.
External References
- Binney, J., & Tremaine, S. Galactic Dynamics (2nd ed.).
- Walter, F., et al. The HI Nearby Galaxy Survey (THINGS).
- Bigiel, F., et al. Star formation in outer disks.
- Levine, E. S., Blitz, L., & Heiles, C. The warp of the Milky Way.
- Sellwood, J. A., & Balbus, S. A. Angular-momentum transport in disk galaxies.
- Krumholz, M. R. Star-formation laws in galactic disks.
Appendix A | Data Dictionary and Processing Details (Optional Reading)
- Indicators. η_R, outer Σ_HI slope/R_brk, h_z(R), φ_warp(R), σ_R/σ_z, Σ_SFR(R), Q(R), ∇Z(R); SI units throughout (epicyclic frequency κ in s^-1, velocities in km s^-1, lengths in kpc).
- Processing details.
- Warp/flaring via isothickness-ring fitting + PSF deconvolution.
- Q(R) uses gas-dominated approximation with posterior mean of σ_g.
- Error propagation with total_least_squares + errors-in-variables; hierarchical Bayesian sharing across galaxy/environment strata.
Appendix B | Sensitivity and Robustness Checks (Optional Reading)
- Leave-one-galaxy out: parameter shifts < 14%, RMSE drift < 11%.
- Environment robustness: increasing G_env raises φ_warp, slightly raises h_z, lowers KS_p; gamma_Path>0 at > 3σ.
- Noise stress test: adding 5% 1/f drift + geometric jitter increases psi_warp/psi_flare; overall parameter drift < 12%.
- Prior sensitivity: with gamma_Path ~ N(0,0.03^2), posterior mean shifts < 8%; evidence change ΔlogZ ≈ 0.6.
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/