Morten Magnusson · Symbiose Research, Sandnes, Norway · ORCID: 0009-0002-4860-5095 · June 2026 · CC-BY-4.0
Status: Background-only tests at current precision show no statistically significant deviation from ΛCDM: the fsσ8 signal collapsed from 2.20σ (pre-DESI DR2) to 0.68σ after DESI DR2, and the Variant H MCMC returns ΔAIC = +4.05 (ΛCDM preferred). The perturbation-sector discriminants (P1, P3) remain untested; decisive outcomes require Stage-IV lensing (Euclid DR1, Rubin LSST, SO × Euclid). EFC therefore remains a candidate extension of ΛCDM pending both CMB likelihood validation and Stage-IV tomography. Predictions below are pre-registered: each has an observable, a quantitative threshold, a reproducible test script or DOI-sealed artefact, and a falsification criterion. A testable model must define where it fails — the dedicated falsification section below lists F7–F9 that kill the perturbation sector cleanly.
April 2026 update (v2.0). Two structural predictions added: P7 — H0 three-window decomposition (32113399, 2026-04-28) reframes the Hubble tension as a regime-mismatch artefact (Planck L0, DESI L1, SH0ES L2); P8 — falsified bar-instability criterion (32101111, 2026-04-25) shows EFC's Π bar-criterion is falsified on N=43 SPARC (AUC=0.217, 0/12 bars), with Πmin retained as an independent disk-state parameter. P2–P4 are constrained by the proven coupling-structure closure of the growth-sector (32084670): fσ8=0.43 and S8≈0.82 (robust, down) are fixed by the proven coupling-structure closure (no free-parameter escape route). The α-parameter is independently constrained to α ∈ [−0.72, −0.68] via non-MCMC analysis (32101213), consistent with both blind freezes (−0.689, −0.702). Latest validation-ledger audit: VAL-2026-006.
The Gap Analysis says what we do not yet know. The Validation Ledger says what has already been tested. This page says what we claim will happen — in Stage-IV data — so that external reviewers can test EFC without reading the full theory stack. Each prediction is structured as:
Grounded in evidence/ (GitHub):
01_hypothesis,
05_results,
06_falsification,
benchmark_table.json.
Grouped by status, not just test-class: predictions already confronted with real data (a verdict exists) are separated from those sealed and awaiting their decisive Stage-IV dataset. Awaiting predictions show only their test class — no verdict badge — to avoid implying a result before the data arrives.
| ID | Observable | EFC | ΛCDM | Data used | Verdict | Seal |
|---|---|---|---|---|---|---|
| P4 | Cosmic shear S8 | ≈0.82 (robust, shifted downward; Σ=μ(1+η)/2 with η→1 ⇒ Σ≈0.99<1). The 0.847 ± 0.015 value required Σ∈[1.03,1.07] (the η∈[1.05,1.15] boost = 0% robust) | 0.811 ± 0.006 (Planck) | DES Y6 (0.789), KiDS-Legacy (0.815) | PASS/mild | 32013738 |
| P5 | Horndeski no-go | EFC reaches (μ < 1 ∧ Σ > 1) only via the fragile η-boost (η-dependent, 0% robust per 32037990). Robust EFC has Σ≈μ<1, outside the forbidden quadrant — does not exclude Horndeski | Allowed | Parameter scan (done) | FRAGILE | 32037990 |
| P6 | Background sign lemma | ΔE²(z) ≤ 0 ∀ z > 0 | Neutral | reproduce_efc.py |
PROVEN | 31333414 |
| P8 | Bar-instability Π criterion | Πmin falsified as a bar predictor (AUC=0.217, captures 0/12 bars, N=43 SPARC); retained as independent disk-state parameter | ELN: ε = Vmax/√(GMd/Rd) > 1.1 | SPARC + S4G + Galaxy Zoo | FALSIFIED | 32101111 |
| ID | Observable | EFC | ΛCDM | Awaiting | Status | Seal |
|---|---|---|---|---|---|---|
| P1 | Σeff(z) lensing crossover | ≈ flat in z (robust; η→1 ⇒ Σ≈μ≈0.99, near-GR, monotonic). Sign change at z ≈ 0.44 is fragile (η-dependent, 0% robust per 32037990) | Monotonic | Euclid DR1 tomography (Oct 2026) | SEALED — awaiting; kill-test class (fragile) | 32037990 |
| P2 | fσ8(z = 0.7) | 0.430 (partial existing data: DESI DR1 z=0.706 = 0.413 ± 0.029, mildly favours EFC) | 0.449 | DESI DR2 full-shape RSD | SEALED — awaiting; damage-test class | 32013156 |
| P3 | EGEFC/EGGR | ≈1 (robust; η→1 ⇒ no enhancement). 1.086 ± 0.012 at kc ≈ 0.05 h/Mpc is fragile (η-dependent, 0% robust per 32037990) | 1.000 ± 0.01 | SO × Euclid DR2 (~2027) | SEALED — awaiting; kill-test class (fragile) | 32023788 |
| P7 | H0 three-window decomposition | Triple-null test: EFC predicts non-null in all three windows. H0L0≈67.5, H0L1≈69.5, H0L2≈73.5 is an interpretive mapping, not the paper's decomposition | Single H0; tension persists | Disaggregated Planck + DESI + SH0ES test | SEALED — awaiting; structural | 32113399 |
Claim. The non-monotonic Σeff(z) crossover at z ≈ 0.44 (enhancement at z < 0.4, suppression at z > 0.5) requires Σ > 1 at low z — which comes from the gravitational-slip boost η ∈ [1.05, 1.15], classified 0% robust (fragile) by EFC's own perturbation-sector analysis (32037990). The crossover values below are therefore tagged fragile (η-dependent, 0% robust per 32037990). The robust EFC (η→1; slip terms ελ, εK cancel under screening) gives Σ ≈ μ ≈ 0.99 flat in z ⇒ no crossover (near-GR, monotonic). This profile is absent in ΛCDM and in standard QS Horndeski models with αT=0.
| z | Σeff | Deviation |
|---|---|---|
| 0.10 | 1.026 | +2.6% |
| 0.29 | 1.008 | +0.8% |
| 0.44 | 1.000 | crossover |
| 0.58 | 0.994 | −0.6% |
| 0.87 | 0.988 | −1.2% |
| 1.21 | 0.985 | −1.5% |
Test. Euclid DR1 tomographic cosmic shear (4+ z-bins, Oct 21, 2026). Falsifier (F9, fragile branch only). A monotonic Σeff(z) across all bins with no sign change inside z ∈ [0.3, 0.6] kills only the fragile (η-boosted) crossover branch — a monotonic result is consistent with the robust EFC prediction (Σ ≈ μ ≈ 0.99 flat, near-GR). Source: evidence/05_results.md R8 · DOI 32037990, Result 3, Fig. 1; robustness per same DOI.
Claim. The regime-transition growth model predicts fσ8(z=0.7) = 0.430 vs ΛCDM 0.449. Joint BAO distance prediction: DH/rd(z=0.7) = 19.797 vs 20.719; DH/rd(z=1.0) = 16.527 vs 17.466.
Test. DESI DR2 full-shape RSD at z ∼ 0.5–0.7 (release pending 2026). Falsifier. Measured fσ8(z=0.7) > 0.449 at > 3σ — i.e. consistent with ΛCDM at high significance — damages but does not kill EFC (point prediction, not structural). Source: evidence/05_results.md R5, R8 · DOI 32013156. Growth model anchored to the DOI-verified existing fσ8 compilation: 6dFGS (10.1111/j.1365-2966.2012.21136.x), SDSS-MGS (10.1093/mnras/stu2693), BOSS DR12 (10.1093/mnras/stx721), VIPERS (10.1051/0004-6361/201526553), FastSound (10.1093/pasj/psw029) — EFC fits it at χ²r=0.340 (α=−0.68) vs ΛCDM 0.554; the DESI DR2 test above remains the decisive blind test.
Claim. Galaxy–CMB-lensing cross-correlation combined with RSD produces the gravitational slip estimator EG. The EG enhancement EGEFC/EGGR = 1.086 ± 0.012 at kc ≈ 0.05 h/Mpc and zeff ≈ 0.5 rests on the gravitational-slip boost η ∈ [1.05, 1.15], which EFC's own perturbation-sector robustness analysis (32037990) classifies as 0% robust (fragile). The 1.086 value is therefore tagged fragile (η-dependent, 0% robust per 32037990). The robust EFC prediction (η→1; slip terms ελ, εK cancel under cosmological screening) gives Σ = μ ≈ 0.99 < 1 ⇒ EG ≈ 1 (no enhancement). The robust prediction does not require EG > 1.
Fragile pass window (η-dependent): [1.03, 1.14]. Test. Simons Observatory CMB lensing × Euclid DR2 galaxy catalogue (~2027–2028). Source: DOI 32023788, sealed 15 Apr 2026 with SHA-256 falsifier; robustness per DOI 32037990.
Claim (derivation result, not data-fit). The robust EFC growth sector gives Σ = μ(1+η)/2 with η→1 ⇒ Σ ≈ 0.99 < 1, so S8 shifts slightly downward to S8 ≈ 0.82 (DOI 31188193: “S8 shift downward… consistent with the S8 tension”). The earlier S8 = 0.847 ± 0.015 value (cosmic shear ξ+ enhancement of ~8%, requiring Σ ∈ [1.03, 1.07]) depended on the η ∈ [1.05, 1.15] boost, which is 0% robust / fragile. New canonical: S8 ≈ 0.82 (robust, down).
Test. Rubin LSST DP2 (Jul–Sep 2026); DES Y6 + KiDS Legacy via RCMP. Comparison. S8 ≈ 0.82 vs DES Y6 0.789 (~1–1.5σ) and KiDS-Legacy 0.815 (< 0.5σ) — PASS/mild. Falsifier (F4). DP2 + Euclid DR1 combined return S8 consistent with Planck ΛCDM (0.811 ± 0.006) at < 1σ — EFC loses motivation. Source: DOI 32013738, sealed with SHA-256 falsifier; S8-direction per DOI 31188193.
Claim. Standard quasi-static Horndeski with αT=0 and cs² > 0 cannot produce μ < 1 and Σ > 1 simultaneously — the action forces Σ ≤ μ universally. EFC was claimed to break this only by reaching the forbidden (μ < 1, Σ > 1) quadrant, which requires the gravitational-slip boost η > 1 (the Σ > 1 piece) — classified 0% robust (fragile) per 32037990. The robust EFC has Σ ≈ μ < 1 (both suppressed, η→1), so it does not occupy the forbidden quadrant and does not exclude Horndeski.
Test. Full numerical scan of (αB, αM) parameter space (done, 135,000 points; 0 Horndeski solutions vs 15 EFC solutions — the 15 EFC solutions all sit in the fragile η-boosted region). Implication (doubly-conditional). EFC distinguishes itself from Horndeski only via the fragile η-boost. The earlier “if P1+P3 are confirmed ⇒ standard Horndeski is excluded” wording is now doubly-conditional: both P1 and P3 are fragile / η-dependent, so the exclusion holds only if both fragile branches survive Stage-IV. Source: evidence/05_results.md R9 · DOI 32037990, Result 1; robustness per same DOI.
Claim. ΔE²(z) ≤ 0 for all z > 0, i.e. HEFC(z) ≤ HΛCDM(z). Reduced Hubble friction enhances growth; analytically proven (Lemma 1) and numerically verified at A ∈ {0.01, 0.1, 1.0, 5.0}.
Reproducibility. python reproduce_efc.py — test sign_lemma_A=*.
Source: DOI 31333414, Lemma 1.
Claim. The Hubble tension is not a free-parameter degeneracy but a
regime-mismatch artefact. EFC predicts that Planck (L0 background), DESI BAO
(L1 transition), and SH0ES (L2 perturbation) measure H0 in distinct regime
windows that do not need to coincide. The three-window decomposition
(thermal / geometric / structural redshift) is a synthesis of existing EFC results, not a new
derivation — the projection Pξ is specified to first order only. The triplet
H0L0≈67.5, H0L1≈69.5, H0L2≈73.5 km/s/Mpc
is an interpretive mapping, not the paper's decomposition.
The atlas role for H0_tension was upgraded 2026-04-29 from
addresses_open to proposes_resolution.
Test. Joint regime-disaggregated chain on Planck + DESI DR2 BAO + SH0ES
+ Euclid DR1 shear (three-window decomposition per DOI
32113399).
Falsifier (triple-null test). EFC predicts a non-null signal in all three windows;
a triple-null result consistent with ΛCDM in every window is a clean falsification.
Source: DOI 32113399
(2026-04-28); validation candidate vc_e36e011d1270.
Result. EFC's Π bar-criterion ΠEFC = σR·κeff/(3.36·G·Σ) < 1 (with κeff incorporating the entropy-gradient correction κ2eff = κ2GR + κ2S-flow) was tested on N = 43 SPARC galaxies and is falsified as a bar predictor: AUC = 0.217 (anti-correlated), capturing 0/12 bars. Πmin is retained not as a bar predictor but as an independent disk-state parameter (ρ[Π, logΣ] = −0.71, ρ[Π, fgas] = +0.65, n = 112).
Test. Cross-population test against SPARC (N = 43 with the bar label; 175 in the
rotation-curve sample), S4G (~2300), Galaxy Zoo bar-fractions; protocol pre-registered as
vc_140e79363cbe.
Source: DOI 32101111
(2026-04-25), “A Falsified Bar-Instability Criterion Reveals an Independent Disk-State Parameter”.
Included here explicitly for honesty: the Variant H entropy-gradient MCMC against DESI DR2 BAO + fσ8 + H(z) + SNIa (40 bins) returns ΔAIC = +4.05, ΔBIC = +3.94. ΛCDM is preferred by current background data. S0 = 0.210 ± 0.141 is consistent with zero at 1.5σ. The σ8 shift is only −1.2%. This does not falsify EFC (the signal may sit below present sensitivity, and the perturbation-sector discriminants P1/P3 remain untested), but it sets a quantitative baseline: background-only tests at current precision do not favour EFC. Source: evidence/05_results.md R7 · DOI 32037990, Result 4.
Each prediction is tied to an explicit falsifier. The KILL-level entries (F1, F7–F9) would invalidate the perturbation-sector mechanism; DAMAGE-level entries (F4–F6) would reduce scope without disproving the framework. Full definitions live in evidence/06_falsification.md.
| ID | Type | Observable | Threshold | Kills which prediction | Status |
|---|---|---|---|---|---|
| F1 | KILL | CMB Cℓ | |ΔCℓ/Cℓ| > 0.1% | Framework (L0 limit) | Sanity pass, likelihood pending |
| F2 | KILL | μ0 | μ0 > 1 at 3σ | Entropy mechanism | Excluded by existing data |
| F3 | KILL | Void ISW / lensing | >5% deviation | Regime boundary (L0/L1) | Planned |
| F4 | DAMAGE | S8 tension | < 1σ across Stage-IV | P4 motivation | Monitoring (2–3σ now) |
| F5 | DAMAGE | Unified χ² | Δχ² > +5 | Global fit | Current +1.72 |
| F6 | DAMAGE | SPARC win rate | < 40% | Galactic sector | Current 60.2% |
| F7 | KILL | Gravitational slip η | η = 1 at 3σ across Stage-IV | P1, P3 (slip sector) | Untested |
| F8 | KILL | (μ, Σ) region | Zero solutions in scan | P3, P5 (fragile η-branch) | 15 solutions found (all η-boosted) |
| F9 | KILL | Σeff(z) profile | Monotonic, no crossover | P1 (fragile η-branch; monotonic is consistent with robust EFC) | Pre-registered, awaiting Euclid DR1 |
| Survey / Release | Date | Tests | Prediction at stake |
|---|---|---|---|
| DESI DR2 full-shape RSD | 2026 | fσ8(z=0.5–0.7), DH/rd | P2 |
| Rubin LSST DP2 | Jul–Sep 2026 | Early shear, S8, ξ+ | P4 |
| Euclid DR1 | Oct 21, 2026 | Tomographic Σeff(z), η, EG | P1, P3, F7 |
| SO × Euclid | ~2027–2028 | EG at kc ≈ 0.05 h/Mpc | P3 |
| DESI DR3 | ~2027–2028 | Full RSD, Lyα BAO, high-z growth | P2 (extended) |
| Planck plik_lite TTTEEE | Ongoing | Full CMB likelihood | F1 (framework-level) |
| Joint Planck + DESI DR2 + SH0ES + Euclid DR1 | 2026–2027 | Regime-disaggregated H0 chain | P7 |
| SPARC + S4G + Galaxy Zoo cross-population | Available now | Bar fraction fbar(M*, σR, κeff) | P8 |
| DES Y6 + KiDS Legacy (RCMP) | 2026 | L2 weak lensing via RCMP protocol | P3, P4 |
Every prediction above either reproduces deterministically from the repository (reproduce_efc.py, reproduce_bao.py, reproduce_sparc.py, reproduce_cmb_sanity.py) or is SHA-256 sealed on figshare with the falsifier locked pre-data. Full binding: evidence/benchmark_table.json.
Coverage today: 88/88 reproducibility checks across four scripts
(fsσ8 31/31, BAO 11/11 diagonal, SPARC 12/12, CMB sanity 24/24,
plus the minimal simple/run.py 10/10).
Full Boltzmann-solver CMB likelihood remains the single outstanding KILL-level gap — see
Gap Analysis §2 KC.
| Most distinctive (fragile) prediction | P1 — lensing crossover at z ≈ 0.44. Structurally distinctive but fragile: the crossover is the η-boost signature (η-dependent, 0% robust per 32037990). Robust EFC predicts a near-flat (monotonic, ≈GR) Σeff(z). Directly testable in Euclid DR1 (Oct 2026). |
| Soonest test | P2 (DESI DR2 RSD, 2026). First opportunity to check a sealed EFC point prediction against fresh data. |
| Cleanest falsifier | F9 — monotonic Σeff(z). If Euclid DR1 sees no sign change, the fragile (η-boosted) P1 branch is dead — but a monotonic result is consistent with the robust EFC (≈GR) prediction. |
| Known weakness | Variant H MCMC (R7): ΔAIC = +4.05 against DESI DR2 background data. ΛCDM is preferred on current background-only tests. |
| Single outstanding gate | Full CMB likelihood (F1). Sanity checks pass, but plik_lite TTTEEE with hi_class/CLASS patch is required before any of P1–P4 can be considered “accepted”. |
| Falsified criterion | P8 (bar-instability). EFC's Π bar-criterion is falsified on N=43 SPARC (AUC=0.217, 0/12 bars). Πmin survives only as an independent disk-state parameter (ρ[Π, logΣ]=−0.71, ρ[Π, fgas]=+0.65, n=112) — not as a bar predictor. |
| Strongest reframing | P7 (H0 three-window). The Hubble tension is restructured rather than resolved: SH0ES, Planck and DESI never measured the same quantity. Atlas role upgraded from addresses_open to proposes_resolution. |
| Structural lock | Growth-sector coupling-structure closure (DOI 32084670): fσ8=0.43 and S8≈0.82 (robust, down) are constrained by the proven coupling-structure closure (unique μ/Σ under EBE) — no free-parameter escape route remains. |
© 2026 Energy-Flow Cosmology Initiative · Predictions — pre-registered, SHA-256 sealed, reproducible