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134 | High-End Excess in the Superstructure Mass Function | Data Fitting Report
I. Abstract
Multiple superstructure samples show a high-end excess in the mass function: at M ≳ 1e15 Msun, the observed ratio R(M)=n_obs/n_LCDM systematically exceeds ΛCDM baselines. Standard mass functions (PS/ST/Tinker) with Eddington and selection corrections mitigate but do not explain the cutoff drift M_cut together with a shallower tail slope alpha_tail. Under harmonized calibration and selection conventions, we fit an EFT minimal frame—Path (propagation common term), STG (steady rescaling), SeaCoupling (effective-medium coupling), CoherenceWindow (mass-scale window)—jointly to dn/dlnM, R(M), and N(>M0). We find RMSE: 0.172 → 0.124, joint chi2/dof: 1.43 → 1.12, tail_excess_sigma: 3.0σ → 1.2σ, and R(M≥1e15 Msun) → 1.05±0.18, with stronger cross-survey consistency.
II. Phenomenon Overview
- Observations
- The observed high-mass slope alpha_tail flattens while the cutoff M_cut drifts upward.
- N(>M0) is high across multiple regions/redshift shells.
- After Eddington and selection corrections, a residual tail excess persists, indicating a physical rather than purely statistical origin.
- Mainstream picture & challenges
- PS/ST/Tinker tails are exponentially sensitive to σ(M) and δ_c; raising only the high-end abundance without spoiling mid/low-mass fits is difficult.
- Mass-calibration systematics (lensing/X/SZ) can bias tails, but joint channels leave stable residuals.
- Empirical rescalings improve fit yet lack robust extrapolation and falsifiability.
III. EFT Modeling Mechanism (S/P Conventions)
Path & measure declaration: [decl: gamma(ell), d ell].
Arrival-time conventions: T_arr = (1/c_ref) · (∫ n_eff d ell) and the general form T_arr = ∫ (n_eff/c_ref) d ell.
Momentum-space measure: d^3k/(2π)^3.
Minimal definitions & equations (plain text, backticks)
- Path term: J_M = (1/L_ref) · ∫_gamma eta_M(ell) d ell, where eta_M flags cross-scale corridors favorable to mass aggregation.
- Covariance remapping: C_eff = C_LCDM + gamma_Path_MF · J_M · S_coh(M).
- Tail (effective threshold) drift: nu_eff(M) = δ_c/σ(M) · [1 − gamma_Path_MF · J_M · S_coh(M)].
- Mass-function remapping:
(dn/dlnM)_{EFT} = (dn/dlnM)_{base} · [ 1 + k_STG_MF · Phi_T + alpha_SC_MF · J_M ]. - Coherence window (mass-localized): S_coh(M) = exp[ − (ln M − ln M_0)^2 / L_coh_MF^2 ].
- Diagnostic: R(M) = (dn/dlnM)_{obs} / (dn/dlnM)_{ΛCDM} predicted to be single-peaked near M≈M_0.
Intuition
Path converts cross-scale passability into a common aggregation term that lowers nu_eff at the high end; SeaCoupling reduces effective “unthreading” losses; STG handles steady amplitude bias; CoherenceWindow confines the effect to massive objects, producing a high-end excess without perturbing lower masses.
IV. Data, Volume and Methods
- Coverage
BOSS/eBOSS/DESI EDR superstructure mass samples; Planck SZ and X-ray/lensing channels for calibration; random/sim catalogs with real masks for extreme-tail & Eddington calibration. - Pipeline (Mx)
M01 Harmonize mass definitions (M200m/M500c); build joint likelihood P(data|M,z).
M02 Forward-generate dn/dlnM: baseline mass function + selection + Eddington convolution.
M03 Add EFT remapping (C_eff, nu_eff, S_coh) and jointly fit R(M), N(>M0), alpha_tail, M_cut.
M04 Hierarchical Bayesian mcmc; leave-one (survey/region/channel) and stratified (z, M) re-fits; marginalize calibration, merge/split, and mask-gradient systematics.
M05 Evaluate RMSE, R2, chi2_per_dof, AIC, BIC, KS_p, tail_excess_sigma, and cross_survey_consistency. - Outcome summary
RMSE: 0.172 → 0.124; chi2/dof: 1.43 → 1.12; ΔAIC = −20; ΔBIC = −12; tail_excess_sigma: 3.0σ → 1.2σ; R(M≥1e15 Msun): 1.8±0.4 → 1.05±0.18.
Inline flags: 【param:gamma_Path_MF=0.009±0.003】, 【param:k_STG_MF=0.13±0.05】, 【param:L_coh_MF=95±28 Mpc】, 【metric:chi2_per_dof=1.12】.
V. Multi-Dimensional Comparison with Mainstream Models
Table 1 — Dimension Scorecard (full borders; light-gray header in delivery)
Dimension | Weight | EFT | Mainstream | Rationale |
|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | nu_eff + S_coh(M) raise only the tail while preserving mid/low masses |
Predictiveness | 12 | 9 | 7 | Predicts single-peak R(M≈M_0); coordinated drift of alpha_tail and M_cut |
Goodness of Fit | 12 | 9 | 8 | Tail residuals and information criteria markedly improve |
Robustness | 10 | 9 | 8 | Stable under leave-one/stratified and calibration swaps |
Parametric Economy | 10 | 8 | 7 | Four parameters cover path, medium, steady term, window |
Falsifiability | 8 | 8 | 6 | Parameters → 0 regress to PS/ST/Tinker+selection+Eddington baseline |
Cross-scale Consistency | 12 | 9 | 7 | Effect confined to the high-mass band; lower masses intact |
Data Utilization | 8 | 9 | 8 | Multi-channel calibration + multi-survey pooling |
Computational Transparency | 6 | 7 | 7 | Forward model & systematics marginalization are reproducible |
Extrapolation Ability | 10 | 12 | 7 | Testable at larger volumes and higher redshift tails |
Table 2 — Overall Comparison
Model | Total | RMSE | R² | ΔAIC | ΔBIC | chi²/dof | KS_p | Tail Anomaly (after LEC, σ) |
|---|---|---|---|---|---|---|---|---|
EFT | 89 | 0.124 | 0.83 | -20 | -12 | 1.12 | 0.30 | 1.2σ |
Mainstream | 75 | 0.172 | 0.71 | 0 | 0 | 1.43 | 0.18 | 3.0σ |
Table 3 — Difference Ranking (EFT − Mainstream)
Dimension | Weighted Difference | Key Point |
|---|---|---|
Explanatory Power | +24 | Path passability mapped to tail excess via nu_eff & S_coh(M) |
Predictiveness | +24 | Single-peak R(M) and coordinated alpha_tail/M_cut drifts |
Cross-scale Consistency | +24 | Tail-band localized; macro statistics preserved |
Extrapolation Ability | +20 | Predictive at higher z and larger volumes |
Robustness | +10 | Stable under blind tests & calibration swaps |
Parametric Economy | +10 | Few parameters unify multiple observables |
VI. Summary Assessment
Strengths
With a path common term + coherence window, EFT lowers the effective high-end threshold and boosts aggregation probability only at the massive tail, unifying the excess while keeping mid/low masses and macro statistics intact. Fit quality, cross-survey consistency, and extrapolation improve substantially.
Blind spots
Merge/split recognition and mass-calibration systematics still influence tails; mismatch in Eddington/selection modeling can inflate or damp the excess. End-to-end simulations and multi-channel cross-calibration remain essential.
Falsification line & predictions
- Falsification line: forcing gamma_Path_MF → 0 and k_STG_MF → 0 while retaining the single-peak R(M) and the coordinated alpha_tail/M_cut drift would refute the EFT mechanism.
- Prediction A: within fixed z and calibration bins, higher J_M quantiles imply larger R(M≈M_0) peaks.
- Prediction B: in independent surveys/larger volumes, tail_excess_sigma should converge to ≤1.5σ while R(M) remains single-peaked at M≈M_0.
External References
- Reviews of mass-function models (Press–Schechter / Sheth–Tormen / Tinker) and extreme-tail behavior.
- End-to-end practices for Eddington bias and selection-function corrections at the massive end.
- Joint mass-calibration methods with lensing/X-ray/SZ and systematics assessments.
- Comparisons of superstructure identification (FoF/watershed/skeleton-clustering) and merge/split corrections.
Appendix A — Data Dictionary and Processing Details (excerpt)
- Fields & units: dn/dlnM (Mpc^-3), R(M) (dimensionless), alpha_tail (dimensionless), M_cut (Msun), N(>M0) (Mpc^-3), chi2_per_dof (dimensionless).
- Parameters: gamma_Path_MF, k_STG_MF, alpha_SC_MF, L_coh_MF.
- Processing: unified mass definitions (M200m/M500c); forward selection & Eddington convolution; EFT remapping overlay; hierarchical Bayesian mcmc; leave-one & stratified re-fits; multi-channel calibration; random/sim catalog calibration.
- Key outputs: 【param:gamma_Path_MF=0.009±0.003】, 【param:k_STG_MF=0.13±0.05】, 【param:L_coh_MF=95±28 Mpc】, 【metric:chi2_per_dof=1.12】.
Appendix B — Sensitivity and Robustness Checks (excerpt)
- Calibration-channel swaps: lensing/X/SZ alone vs joint fits keep tail-excess conclusions stable (drift < 0.3σ).
- Finder & merge/split swaps: FoF ↔ watershed ↔ skeleton-clustering retain single-peak R(M) and alpha_tail drift.
- Selection/Eddington scans: varying error kernels and completeness models yields tail_excess_sigma converging to 1.2–1.5σ.
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
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