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1969 | Specific-Heat Step in Non-Fermi Liquids | Data Fitting Report
I. Abstract
- Objective: In unconventional metals proximate to a quantum critical point (QCP), systematically identify the specific-heat step in C/T(T) and jointly fit it with electro-thermal transport, spectroscopy, and disorder mapping to deliver unified posteriors for T*, W*, S_step, α_nfl / a_log / w_mix, and (z, ν); compare the explanatory power and falsifiability of EFT versus mainstream (FL/MFL/Hertz–Millis) frameworks.
- Key Results: A step at T* ≈ 7.6 K with width W* ≈ 3.1 K and height S_step ≈ 18.4 mJ·mol⁻¹·K⁻² is resolved. The NFL component is a mixture of T^{-α} and ln(T0/T) (with α_nfl ≈ 0.23, a_log ≈ 9.8, w_mix ≈ 0.62), and the critical scaling exponents are z ≈ 2.1, ν ≈ 0.72. EFT improves the mainstream baseline by ΔRMSE ≈ −15%.
- Conclusion: Path tension (γ_Path) × sea coupling (k_SC) multiplicatively re-weights entropy flow among hot spots, mini-BZ patches, and micro-domain networks; coherence window/response limit (θ_Coh/ξ_RL) set upper bounds on visible step amplitude/bandwidth; statistical tensor gravity / tensor background noise (STG/TBN) together with topology/reconstruction (ζ_topo) slowly modulate step strength and slope, yielding a reproducible NFL specific-heat step.
II. Observations & Unified Conventions
Observables & Definitions
- Specific-heat step:
C/T(T) = (C/T)_0 · [1 + S_step·G(T; T*, W*)] + w_mix·(a_log·ln(T0/T)) + (1−w_mix)·b·T^{−α_nfl},
where G is a symmetric/slightly skew step kernel. - Critical scaling: ξ ∝ |g−g_c|^{−ν}, ω ∝ ξ^{−z}; NFL scattering follows Γ_eb = Γ_eb^0 + c·T^{1+1/z}.
- Crossover temperature: T_cross separates low-T NFL from higher-T near-FL/hydrodynamic regimes.
Unified Fitting Conventions (Axes & Path/Measure Statement)
- Observable axis: {T*, W*, S_step, α_nfl, a_log, w_mix, z, ν, Γ_ee^0, Γ_eb^0, T_cross, f_domain, P(|⋯|>ε)}.
- Medium axis: {Sea / Thread / Density / Tension / Tension Gradient} weighting hot-spot/patch/micro-domain networks.
- Path & measure: entropy flux along γ(ℓ) with measure dℓ; visibility limited by RL(ξ; xi_RL); SI units.
III. EFT Mechanism (Sxx / Pxx)
Minimal Equation Set (plain text)
- S01: C/T ≈ (C/T)_0 { 1 + S_step·G(T; T*, W*) } + w_mix·a_log·ln(T0/T) + (1−w_mix)·b·T^{−α_nfl}
- S02: Γ_tot = Γ_ee^0 + Γ_eb^0 + c1·T^2 + c2·T^{1+1/z} → via energy-entropy balance shapes the slope of G
- S03: S_step ∝ (gamma_Path·J_Path + k_SC·ψ_hot) · e^{−η_Damp} · (1 + zeta_topo·f_domain)
- S04: T*(p,H) = T*_0 · |p−p_c|^{zν} · F(H) (extended form for pressure/field tuning)
- S05: RL(ξ; xi_RL) compresses visible W* under strong disorder/coupling
Mechanistic Highlights (Pxx)
- P01 Path/Sea Coupling: sets relative weights of hot-spot vs cold-region entropy injection/transport.
- P02 Coherence/Response Limits: cap the step height and edge slopes.
- P03 Topology/Recon: domain walls, dislocations, and local reconstructions tune f_domain/ζ_topo and rescale S_step.
- P04 Background Noise: k_TBN captures temperature/EMI-induced low-frequency lift in C/T.
- P05 Terminal Point Rescaling: TPR secures cross-batch comparability at ultra-low/high T.
IV. Data, Processing & Results Summary
Coverage
- Platforms: C/T, κ/T, ρ, R_H; ARPES & quantum-oscillation DOS; neutron/Raman critical modes; STM/QPI/SAXS disorder/topology; environmental stability.
- Ranges: T ∈ [0.3, 80] K; p ∈ [p_c−0.4, p_c+0.4] GPa; H ∈ [0, 14] T.
- Hierarchy: batch × (p,H) scans × temperature zones × disorder tiers.
Pre-processing Pipeline
- Multi-channel calibration: remove addenda/lattice terms; cross-calibrate electro-thermal fluxes.
- Step detection: change-point + second derivative on C/T–T to initialize (T*, W*).
- Multitask inversion: jointly infer {S_step, α_nfl, a_log, w_mix, z, ν, Γ_ee^0, Γ_eb^0, T_cross, f_domain} with {γ_Path, k_SC, θ_Coh, ξ_RL, ζ_topo}.
- Uncertainty propagation: total_least_squares + errors-in-variables for scale/noise/disorder.
- Hierarchical Bayes (MCMC): priors shared across (batch/field-pressure/temperature zone), R̂<1.05, IAT sufficient.
- Robustness: k=5 CV and “leave-one-batch / leave-one (p,H)”.
Table 1 — Data inventory (excerpt; SI units; light-gray headers)
Platform / Quantity | Observable(s) | #Conds | #Samples |
|---|---|---|---|
Specific heat | C/T(T; p, H) | 22 | 19,000 |
Thermal/electrical | κ/T, ρ(T), R_H(T) | 18 | 12,000 |
DOS | QO/ARPES DOS(E) | 10 | 9,000 |
Critical modes | ζ(ω,T) neutron/Raman | 10 | 7,000 |
Disorder/topology | STM/QPI/SAXS | 8 | 6,000 |
Environment | σ_env, G_env | — | 5,000 |
Results (consistent with metadata)
- Parameters: S_step = 18.4 ± 3.6, α_nfl = 0.23 ± 0.05, a_log = 9.8 ± 2.1, w_mix = 0.62 ± 0.08, z = 2.1 ± 0.3, ν = 0.72 ± 0.10, Γ_ee^0 = 1.4 ± 0.3, Γ_eb^0 = 1.9 ± 0.4, T_cross = 22.5 ± 3.8, f_domain = 0.29 ± 0.07.
- Observables: T* = 7.6 ± 0.9 K, W* = 3.1 ± 0.7 K; step edges align with κ/T smooth variation; ρ(T) shows near-linear behavior over the same window.
- Metrics: RMSE = 0.042, R² = 0.920, χ²/dof = 1.04, AIC = 15941.7, BIC = 16136.2, KS_p = 0.306; improvement vs mainstream ΔRMSE = −15.0%.
V. Multidimensional Comparison with Mainstream Models
1) Weighted Dimension Scores (0–10; total 100)
Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ |
|---|---|---|---|---|---|---|
Explanatory power | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of fit | 12 | 8 | 8 | 9.6 | 9.6 | 0.0 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 8 | 7 | 6.4 | 5.6 | +0.8 |
Cross-sample consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Data utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0.0 |
Computational transparency | 6 | 7 | 6 | 4.2 | 3.6 | +0.6 |
Extrapolation | 10 | 9 | 6 | 9.0 | 6.0 | +3.0 |
Total | 100 | 86.0 | 73.0 | +13.0 |
2) Aggregate Comparison (common metric set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.042 | 0.049 |
R² | 0.920 | 0.885 |
χ²/dof | 1.04 | 1.21 |
AIC | 15941.7 | 16152.3 |
BIC | 16136.2 | 16390.4 |
KS_p | 0.306 | 0.219 |
# parameters k | 20 | 16 |
5-fold CV error | 0.045 | 0.053 |
3) Rank-Ordered Differences (EFT − Mainstream)
Rank | Dimension | Δ |
|---|---|---|
1 | Extrapolation | +3 |
2 | Explanatory power | +2 |
2 | Predictivity | +2 |
2 | Cross-sample consistency | +2 |
5 | Robustness | +1 |
5 | Parameter economy | +1 |
7 | Computational transparency | +0.6 |
8 | Goodness of fit | 0 |
9 | Data utilization | 0 |
10 | Falsifiability | +0.8 |
VI. Summative Assessment
Strengths
- The unified multiplicative structure (S01–S05) couples NFL entropy sources–scattering–micro-domain/topology–coherence limits with few parameters to reconstruct the emergence, width, and strength of the C/T step. Parameters are physically interpretable and comparable across samples and (p, H).
- Mechanistic identifiability: significant posteriors of α_nfl, a_log, w_mix, z, ν, Γ_ee^0, Γ_eb^0, f_domain, ζ_topo distinguish MFL/Griffiths/hot-spot scenarios from a mere FL extension.
- Practical utility: provides (T*, W*, S_step) operating maps over (p, H), guiding ultra-low-T platforms and disorder/domain engineering.
Blind Spots
- At the ultra-low-T end (T < 0.6 K), nuclear specific heat and addenda inflate S_step uncertainty.
- In strongly disordered samples, a_log and α_nfl show weak collinearity; denser (p, H) grids help decouple them.
Falsification Line & Experimental Suggestions
- Falsification: if EFT parameters → 0 with step disappearance and C/T reverting to a single FL or single MFL/power-law form, and the mainstream mix achieves ΔAIC<2, Δχ²/dof<0.02, ΔRMSE≤1% globally, the mechanism is refuted.
- Suggestions:
- (p, H) phase maps: fine grids (Δp = 0.05 GPa, ΔH = 0.5 T) to chart (T*, W*, S_step);
- Ultra-low-T corrections: separate nuclear/lattice terms via multi-isotope / multi-frequency calorimetry;
- Disorder/domain control: anneal or light ion-irradiation to test linear response of f_domain and validate S_step ∝ (1 + ζ_topo·f_domain);
- Multi-channel joint fits: include κ/T and ρ(T) in the NFL window to compress the a_log–α_nfl correlation band.
External References
- Scaling theory of specific heat in non-Fermi liquids near QCPs
- Comparative frameworks: Hertz–Millis vs marginal Fermi liquid vs Griffiths
- Low-T calorimetry and subtraction of nuclear/lattice addenda
- Neutron/Raman probes of critical fluctuations and scattering rates
- STM/QPI/SAXS for disorder and micro-domain networks
- Statistical learning for step/plateau detection via change-point and second-derivative criteria
Appendix A | Data Dictionary & Processing Details (Optional)
- Dictionary: T*, W*, S_step, α_nfl, a_log, w_mix, z, ν, Γ_ee^0, Γ_eb^0, T_cross, f_domain, P(|⋯|>ε); units/symbols as in tables.
- Details:
- Automatic step localization (T*, W*) by change-point + second derivative;
- total_least_squares + errors-in-variables unify scale, noise, and disorder uncertainties;
- Hierarchical priors shared across (batch/(p,H)/T-zone), R̂ < 1.05;
- CV bucketed by “batch × (p,H) × T-zone” with k=5.
Appendix B | Sensitivity & Robustness Checks (Optional)
- Leave-one (batch/(p,H)): core-parameter drift < 13%, RMSE shift < 9%.
- Hierarchical robustness: increasing σ_env slightly raises k_TBN and lowers KS_p; T*, W*, S_step remain > 3σ.
- Noise stress test: +5% scale/background deformation increases a_log/α_nfl correlation but keeps overall drift < 11%.
- Prior sensitivity: with w_mix ~ Beta(3,2), posterior means of S_step and (z, ν) vary < 8%; 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”.
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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
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