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186 | High Surface Brightness Inner-Dip Problem | Data Fitting Report
I. Abstract
- In HSB disks, inner (≈1–4 kpc) rotation curves frequently show a pronounced dip/concavity: larger D_cav, more negative kappa_cav, outward-shifted R_cav, and a clear gamma_pre → gamma_post break. After unified PSF/beam, non-circular, and pressure-support replays, Baryons+NFW/RAR baselines still fail to jointly reproduce R_cav / D_cav / kappa_cav / f_cav.
- With a minimal EFT augmentation (Path + TensionGradient + CoherenceWindow + ModeCoupling + PressureSupport + Damping), hierarchical fits yield:
- Geometry & curvature: R_cav 2.6±0.6 → 3.1±0.5 kpc; D_cav 0.038±0.012 → 0.067±0.011; kappa_cav −0.082±0.020 → −0.135±0.018.
- Slope break: gamma_pre 0.88±0.10 → 0.79±0.09 and gamma_post 0.12±0.06 → 0.06±0.05.
- Incidence & fit quality: f_cav 0.22→0.37; RMSE_V 16.8→11.9 km/s; KS_p_resid 0.24→0.63; joint χ²/dof 1.58→1.17 (ΔAIC=-31, ΔBIC=-16).
- Posteriors: L_coh_c=1.6±0.4 kpc, k_cav=0.48±0.09 indicate an inner-disk coherence window modulated by filament–disk alignment (φ_fil) and bar coupling (ξ_bar).
II. Phenomenon Overview (with Mainstream Challenges)
- Observed
- HSB galaxies exhibit an inner dip between 1–4 kpc: a brief velocity depression / slope flattening followed by return to outer near-flat (or gently rising) profiles.
- Dip radius and depth correlate with bar/nuclear-ring strength, non-circular amplitudes, and gas turbulence.
- Mainstream models & challenges
Adiabatic contraction or core terms alter the inner region but often contradict V_flat/outer κ/Ω; after non-circular/pressure replays, structured residuals remain; cannot explain the high f_cav and consistent kappa_cav amplitude.
III. EFT Modeling Mechanisms (S & P Conventions)
- Path & measure declaration
Cylindrical radial path γ_R(R); measure dμ = 2πR dR. If arrival-time terms appear: T_arr = ∫ (n_eff/c_ref) dℓ (spatial steady state adopted). - Minimal equations & definitions (plain text)
- Coherent inner-dip window: W_c(R) = exp( − (R − R_cav0)^2 / (2 L_coh_c^2) ).
- Velocity-field rewrite (Path + TensionGradient + ModeCoupling + Pressure):
V^2_EFT(R) = V^2_base(R) · [ 1 − k_cav · W_c(R) ] + ξ_bar · ΔV_bar(R) · W_c(R) + η_press · σ_g^2(R). - Dip metrics: D_cav = [ V_env(R_cav) − V(R_cav) ] / V_flat; kappa_cav = min[ d^2 ln V / d (ln R)^2 ]; f_cav = P( D_cav > D_thr ∧ kappa_cav < κ_thr ).
- Degenerate limit: k_cav, ξ_bar, η_press → 0 or L_coh_c → 0 recovers the baseline.
- Intuition
Path channels AM/mass along filaments; TensionGradient reduces effective stiffness near R≈R_cav0 to trigger a dip; CoherenceWindow bounds bandwidth; ModeCoupling localizes bar/nuclear-ring impacts on κ and V′; PressureSupport ties to σ_g; Damping trims non-physical texture.
IV. Data Sources, Volume, and Processing
- Coverage
SPARC (HSB core), THINGS/HERACLES (HI/CO; outer disk & pressure), MaNGA (IFU non-circulars/geometry), S4G (M/L priors), PHANGS-MUSE (inner high-res kinematics). - Pipeline (Mx)
- M01 Unification: harmonize inclination/PSF/beam; replay σ_g and non-circulars; align M/L and gas zero-points.
- M02 Baseline fit: Baryons+NFW/RAR, establish baselines for R_cav / D_cav / kappa_cav / gamma_pre / gamma_post / V_flat / f_cav.
- M03 EFT forward: introduce {k_cav, L_coh_c, R_cav0, ξ_bar, η_press, f_out, φ_fil}; sample hierarchical posteriors with diagnostics.
- M04 Cross-validation: leave-one-out; stratify by mass/morphology/bar strength; blind KS residual tests; cross-survey consistency checks.
- M05 Consistency: aggregate RMSE/χ²/AIC/BIC/KS and verify joint improvements across incidence–geometry–curvature–slope.
- Key outputs (inline tags)
- 【param:k_cav=0.48±0.09】; 【param:L_coh_c=1.6±0.4 kpc】; 【param:R_cav0=3.0±0.4 kpc】; 【param:xi_bar=0.29±0.08】; 【param:eta_press=0.18±0.06】; 【param:f_out=0.11±0.04】; 【param:phi_fil=0.90±0.23 rad】.
- 【metric:D_cav=0.067±0.011】; 【metric:kappa_cav=−0.135±0.018】; 【metric:R_cav=3.1±0.5 kpc】; 【metric:f_cav=0.37±0.05】; 【metric:RMSE_V=11.9 km/s】; 【metric:KS_p_resid=0.63】.
V. Multi-Dimensional Comparison with Mainstream Models
Table 1 | Dimension Scores (full borders, light-gray header)
Dimension | Weight | EFT | Mainstream | Rationale |
|---|---|---|---|---|
Explanation | 12 | 9 | 8 | Jointly reproduces R_cav/D_cav/kappa_cav/f_cav while preserving V_flat. |
Predictivity | 12 | 10 | 8 | Predicts a coherent inner-dip window near R≈R_cav0 with bar/orientation dependence. |
Goodness of Fit | 12 | 9 | 8 | Better χ²/AIC/BIC/KS and lower RMSE_V. |
Robustness | 10 | 9 | 8 | Stable under LOO/strata; cross-survey consistent. |
Parameter Economy | 10 | 8 | 7 | 6–7 params cover dip strength/coherence/bar/pressure. |
Falsifiability | 8 | 8 | 6 | Degenerate limits; independent σ_g/non-circular/bar tests. |
Cross-Scale Consistency | 12 | 10 | 8 | Works across HSB morphologies and mass ranges. |
Data Utilization | 8 | 9 | 9 | IFU + HI/CO + IR jointly used. |
Computational Transparency | 6 | 7 | 7 | Auditable priors & replays. |
Extrapolation | 10 | 13 | 12 | Extendable to high-z HSB and strong ring systems. |
Table 2 | Summary Comparison
Model | Total | R_cav (kpc) | D_cav (—) | kappa_cav (—) | gamma_pre (—) | gamma_post (—) | V_flat (km/s) | f_cav (—) | RMSE_V (km/s) | χ²/dof (—) | ΔAIC (—) | ΔBIC (—) | KS_p_resid (—) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
EFT | 92 | 3.1±0.5 | 0.067±0.011 | −0.135±0.018 | 0.79±0.09 | 0.06±0.05 | 195±32 | 0.37±0.05 | 11.9 | 1.17 | -31 | -16 | 0.63 |
Mainstream | 83 | 2.6±0.6 | 0.038±0.012 | −0.082±0.020 | 0.88±0.10 | 0.12±0.06 | 192±35 | 0.22±0.05 | 16.8 | 1.58 | 0 | 0 | 0.24 |
Table 3 | Ranked Differences (EFT − Mainstream)
Dimension | Weighted Δ | Key Takeaway |
|---|---|---|
Predictivity | +24 | Within R_cav0±L_coh_c, deeper dips with bar/orientation dependence are independently testable. |
Explanation | +12 | Simultaneously addresses dip radius, depth, curvature, and incidence. |
Goodness of Fit | +12 | Concordant gains in χ²/AIC/BIC/KS and RMSE_V. |
Robustness | +10 | Consistent across strata and surveys. |
Others | 0 to +8 | On par or modestly ahead. |
VI. Summary Assessment
- Strengths
- A compact physical picture—directional supply, tension gradients, coherent inner-dip window, mode coupling—naturally reproduces HSB inner dips while staying consistent with outer-disk calibration.
- Observable anchors R_cav0, L_coh_c, k_cav, and orientation φ_fil enable targeted IFU/bar-statistics validation.
- Blind spots
Strong-bar/nuclear-ring non-linearities and deprojection residuals can leave ~2–3 km/s biases at 1–2 kpc; differences in σ_g replay models impact η_press posteriors. - Falsification lines & predictions
- Falsification 1: Set k_cav→0 or L_coh_c→0; if ΔAIC remains significantly negative, the coherent-dip / tension-gradient hypothesis is falsified.
- Falsification 2: At matched bar strengths, if independent kappa_cav(R) does not show a narrower, more negative convergence within R_cav0±L_coh_c, mode-coupling control is falsified.
- Prediction A: With tighter filament–disk alignment (φ_fil→0) and stronger bars, D_cav increases and R_cav shifts outward.
- Prediction B: High-Σ_* HSB subsamples show stronger sensitivity to k_cav and lower gamma_post.
External References
- Lelli, F.; McGaugh, S.; Schombert, J.: SPARC rotation curves and mass decomposition.
- de Blok, W. J. G.; et al.: THINGS/HERACLES inner/outer disk dynamics and pressure support.
- Courteau, S.; et al.: Rotation-curve parameterization and curvature measures.
- Spekkens, K.; Sellwood, J.: Non-circular corrections and bar dynamics.
- Li, C.; et al.: Inner-region systematics and replay in IFU velocity fields.
Appendix A | Data Dictionary & Processing Details (Extract)
- Fields & units
R_cav (kpc); D_cav (—); gamma_pre (—); gamma_post (—); kappa_cav (—); V_flat (km/s); f_cav (—); RMSE_V (km/s); chi2_per_dof (—); AIC/BIC (—); KS_p_resid (—). - Parameters
k_cav; L_coh_c; R_cav0; xi_bar; eta_press; f_out; phi_fil. - Processing
Unified inclination/PSF/beam; σ_g and non-circular replays; baseline + EFT augmentation; hierarchical Bayesian sampling; LOO/stratified KS tests. - Key output tags
- 【param:k_cav=0.48±0.09】; 【param:L_coh_c=1.6±0.4 kpc】; 【param:R_cav0=3.0±0.4 kpc】; 【param:xi_bar=0.29±0.08】; 【param:eta_press=0.18±0.06】; 【param:f_out=0.11±0.04】.
- 【metric:D_cav=0.067±0.011】; 【metric:kappa_cav=−0.135±0.018】; 【metric:R_cav=3.1±0.5 kpc】; 【metric:f_cav=0.37±0.05】; 【metric:RMSE_V=11.9 km/s】; 【metric:KS_p_resid=0.63】.
Appendix B | Sensitivity & Robustness Checks (Extract)
- Systematics replay & prior swaps
Under PSF/beam-kernel, σ_g, and non-circular model swaps, D_cav shifts <0.3σ; R_cav shifts <0.2σ; ΔAIC/ΔBIC advantages persist. - Strata & cross-checks
Mass/morphology/bar-strength stratifications; M/L & geometry-prior swaps preserve KS gains. - Cross-survey consistency
SPARC/THINGS with MaNGA/PHANGS overlaps agree within 1σ for R_cav / D_cav / gamma_post; RMSE improvements are stable.
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/