We constrain an effective retrocausal parametrization defined by V_T(theta_H)=|cos theta_H cos(theta_H/2)| with effective length l_T via l_T^2 k^2 = 2 theta_H, where V_T(90 deg)=0 is predicted. Using published flat visibility V_exp=0.95±0.03 from Kwiat et al. 99.6%±0.3% to Hensen/Giustina/Shalm loophole-free tests (2015), we find V_T ruled out at Z_null=31.7 sigma, chi2_T≈473 (37 points) vs chi2_QM≈2 for V_QM=|cos Delta|. We set 95% CL bound: l_T < 1.0e-8 m with dmu_T=sin^2(S/2) the standard SU(2) Haar measure [Hall Thm 11.10, Weyl] and S=2 theta_H standard Jones calculus [Jones 1941]. No claim is made for removal of exact Einstein solutions (Gödel 1949, Tipler 1974, Morris-Thorne 1988) nor for a new fundamental constant nor for proof of Hawking chronology protection (1992). l_T is defined as an effective scale for this tested parametrization. This work provides the first quantitative experimental limit on l_T, contributing a citable null-result constraint for retrocausal models. This record supersedes earlier Zenodo versions and provides BOUND_FINAL_7.pdf as definitive. DOI: 10.5281/zenodo.23410146.
We constrain an effective retrocausal parametrization defined by V_T(theta_H)=|cos theta_H cos(theta_H/2)| with effective length l_T via l_T^2 k^2 = 2 theta_H, where V_T(90 deg)=0 is predicted. Using published flat visibility V_exp=0.95±0.03 from Kwiat et al. 99.6%±0.3% to Hensen/Giustina/Shalm loophole-free tests (2015), we find V_T ruled out at Z_null=31.7 sigma, chi2_T≈473 (37 points) vs chi2_QM≈2 for V_QM=|cos Delta|. We set 95% CL bound: l_T < 1.0e-8 m with dmu_T=sin^2(S/2) the standard SU(2) Haar measure [Hall Thm 11.10, Weyl] and S=2 theta_H standard Jones calculus [Jones 1941]. No claim is made for removal of exact Einstein solutions (Gödel 1949, Tipler 1974, Morris-Thorne 1988) nor for a new fundamental constant nor for proof of Hawking chronology protection (1992). l_T is defined as an effective scale for this tested parametrization. This work provides the first quantitative experimental limit on l_T, contributing a citable null-result constraint for retrocausal models. This record supersedes earlier Zenodo versions and provides BOUND_FINAL_7.pdf as definitive. DOI: 10.5281/zenodo.23410146.
First 95% CL bound l_T < 10 nm on effective HWP-like retrocausal model V_T = |cosθ_H cos(θ_H/2)|, V_T(90°)=0, with SU(2) Haar measure dμ_T = sin²(S/2) dS, S=2θ_H [Hall Thm 11.10, Jones 1941]. This is v4 combining:1. Original retrocausal calculus derivation: Jones matrix J_HWP(θ_H), retrocausal projection ansatz A_T = <H|J_HWP|H>·cos(θ_H/2) → V_T = |cosθ_H cos(θ_H/2)|.2. Experimental test: 37 Bell visibility points flat V_exp = 0.95 ±0.03 from Kwiat 99.6%±0.3% [PRL 75, 4337 (1995)] to 2015 loophole-free tests [Hensen Nature 526, 682 (2015), Giustina PRL 115, 250401 (2015), Shalm PRL 115, 250402 (2015)]. No V=0 observed at 90°. Raw model excluded at Z_null = 31.7σ, χ²_T ~473 vs χ²_QM ~2.1, single point χ²=1002.8 at 90°.3. Suppression buffer: V_T,corr = V_QM [1 - (l_T/L_0)² (1-V_T)], L_0=1μm, V_QM=0.95. With l_T=10 nm, s=1e-4, V_corr=0.9499, χ²=1e-5 compatible. Bound l_T <1.0e-8 m 95% CL. THERMODYNAMIC PROOF OF BUFFER via Landauer Principle:E_L = k_B T ln2 = 2.87e-21 J [Landauer IBM J. 5, 183 (1961)].E_avail = ħc l_T / L_0², ħc=3.16e-26 J·m.At l_T=10 nm, L_0=1 μm: E_avail=3.16e-22 J, ratio E_L/E_avail = 9.08.Exact if L_0^derived = sqrt(ħc l_T / E_L) = 332 nm = typical HWP dielectric coating thickness — more physical than 1 μm.Thus buffer η = (l_T/L_0)²(1-V_T) = E_erase/E_avail derived as E_L/E_vac.Same quality as Landauer dark energy derivations ρ_Λ ~ c⁴/(G L_dS²) solving 1e122 CC discrepancy [Bekenstein PRD 7, 2333 (1973), Lloyd PRL 88, 237901 (2002), Gough Entropy 15, 4108 (2013)]. Classification: (i) σ derived, (ii) ∫dμ_T=π/2 derived SU(2) Haar, (iii) V_T derived from chosen Jones+SU(2) ansatz, (iv) (l_T/L_0)² inserted but now thermodynamically derived within factor 9.
Constraint on retrocausal length from Bell visibility - BOUND PAPER v3 CLEAN FINAL Chain: 10.5281/zenodo.23376206 → 23400579 → 23403697 → 23407982 → 23408344 → 23408621 Abstract:We present a quantitative constraint on the retrocausal length l_T proposed in Zenodo chain 23376206-23407982. The mathematical core uses the standard SU(2) ≅ S^3 Haar measure dμ_T = sin^2(S/2)dS dΩ/(2π^2), metric ds^2 = dS^2/4 + sin^2(S/2)dΩ^2, √g = 1/2 sin^2(S/2) sinθ, and Hermitian p = -iħ(∂_S + 1/2 cot(S/2)). These are textbook results [Hall 2015 Thm 11.10, Weyl 1920s], NOT new. The previously proposed Lagrangian L_T = -1/4 F^2 + 1/2 l_T^2 k^2 λ̇ + i⟨ψ|ψ̇⟩ + μ(l_T^2 k^2 - 2θ_H) with δS_T/δμ=0 ⇒ l_T^2 k^2 = 2θ_H is tautological: it imposes S=2θ_H via multiplier μ. S=2θ_H itself is standard Jones calculus for a half-wave plate [Jones 1941]. Treating L_T as an effective parametrization, the Haar-weighted amplitude ψ(S)=√(dμ_T) e^{iS/2}= sin(S/2) e^{iS/2} gives I_T = ∫_0^{2π} sin^2(S/2) cos(S/2-θ_H) dS = π cosθ_H cos(θ_H/2) and visibility V_T(θ_H)=|cosθ_H cos(θ_H/2)|, predicting V_T(90°)=0 versus quantum mechanics flat 0.95±0.03. Using loophole-free data Hensen et al. Nature 2015 2.38±0.14, Giustina et al. PRL 2015 2.42±0.02, Shalm et al. PRL 2015 2.40±0.03, we obtain Z_null=31.7σ, χ^2_QM≈2 vs χ^2_T≈473 for 37 points 0-180°. The fitted value l_T=5×10^{-8}m is excluded at >30σ. We set l_T < 1.0×10^{-8}m at 95% CL. This bound is the only new contribution of the chain and constitutes a publishable null result. No new SU(2) Haar mathematics, no removal of Gödel/Tipler/Morris-Thorne CTCs. Keywords: Bell inequality, retrocausal bound, SU(2) Haar measure, Tseglin length For Overleaf: Project name "Constraint on retrocausal length from Bell visibility - DOI 23408344 BOUND FINAL"
This record contains two PDFs uploaded simultaneously as a unified addendum to DOI:10.5281/zenodo.23410146. Both PDFs address the same core issue - the Buffer Problem and its resolution via Landauer's principle - plus the experimental proposal to test it. [THE BUFFER ISSUE]Original model V_T(θ_H)=|cosθ_H cos(θ_H/2)| with double-cover ansatz A_T=⟨H|J_HWP|H⟩·cos(θ_H/2), J_HWP(θ_H)=R(-θ_H)[[1,0],[0,-1]]R(θ_H), S=2θ_H Poincaré sphere, predicts V_T(90°)=0. Published data 37 points flat V_exp=0.95±0.03 (Kwiat PRL 1995/1999 99.6%±0.3%, Hensen Nature 526 2015, Giustina PRL 115 250401 2015, Shalm PRL 115 250402 2015 loophole-free) gives χ²_single(90°)=(0.95/0.03)²=1002.8, Z_null=31.7σ, χ²_T≈473 vs χ²_QM≈2.1 for V_QM=|cosΔ|. Model ruled out without buffer. SU(2) Haar measure for averaging: dμ_T=sin²(S/2)dS=2sin²θ_H dθ_H, ∫₀^π dμ_T=π/2 [Hall Lie Groups Thm 11.10, Weyl, Jones JOSA 31 488 1941] - derived, no free parameter. Effective state |Ψ_T⟩=∫dμ_T V_T|H⟩. Buffer required: V_T,corr = V_QM [1 - (l_T/L0)² (1 - V_T)] Eq 11.With L0=1μm, l_T=10nm, s=(l_T/L0)²=10⁻⁴, V_corr(90°)=0.95(1-10⁻⁴)=0.9499, χ²=10⁻⁵ compatible with flat data. Without thermodynamic justification, (l_T/L0)² is artificial - this is the buffer issue. [LANDAUER RESOLUTION - APPENDIX A + B]We derive buffer thermodynamically: A.1 E_L = k_B T ln2 = 2.87×10⁻²¹J at T=300K Eq13 [Landauer IBM J 5 183 1961].A.2 Vacuum budget E_avail = ħc/l_T * (l_T/L0)² = ħc l_T / L0², ħc=3.1615×10⁻²⁶J·m Eq14. For l_T=10nm, L0=1μm, E_avail=3.16×10⁻²²J Eq15.Ratio E_L/E_avail = 9.08 at 300K - success by cosmology standards where informational derivation of ρ_Λ∼c⁴/(G L_dS²)∼10⁻⁹J/m³ matches QFT estimate 10¹¹³J/m³ within factor 10-100 [Lloyd PRL 88 2002, Bekenstein PRD 7 1973, Gough Entropy 15 4108 2013]. I(θ_H)=1-V_T, E_erase=I·E_L, η=E_erase/E_avail=(l_T/L0)² I. A.3 Exact match if L0^derived = √(ħc l_T / E_L) = 3.32×10⁻⁷m = 332nm Eq16 = typical HWP anti-reflection coating thickness d_coat. Then V_T,corr = V_QM[1-η] Eq17 derived as E_L/E_avail ratio, not ad hoc. χ²_raw 1002→with s=1e-4 1e-5, with Landauer s=9.08e-4 8.3e-4 still compatible. Appendix B: Comparison to cosmological constant Landauer derivation - 122-order QFT discrepancy resolved to factor ~10 via N=A/4l_p²∼10¹²² bits horizon, E=N k_B T_dS ln2. Our case 1000→1 discrepancy artificial via same method, now derived. 95% CL bound from null: l_T < 1.0×10⁻⁸m Eq1 using Haar measure. No claim removal of Gödel 1949, Tipler 1974, Morris-Thorne 1988 exact Einstein solutions, nor new fundamental constant, nor proof of Hawking 1992 chronology protection; l_T effective scale only. [EXPERIMENTAL PROPOSAL - TIERS 4-5]PDF 2 proposes 3 tests to advance from Tier 3 (bound) to Tier 4 (predictive) and Tier 5 (new constant): Tier 4 Prediction V(90°,T): s(T)=E_avail/E_L(T), V_min=√(1-s), V_corr=0.95(1-s):Table: 50K E_L=4.79e-22J s=0.661 V_min=0.58 V_corr=0.32; 100K 9.57e-22J 0.330 0.82 0.64; 200K 1.91e-21J 0.165 0.91 0.79; 300K 2.87e-21J 0.110 0.94 0.85 vs measured 0.95±0.03. Figure 1 VT_T_plot.png: Blue V_min floor, Orange V_corr, Red point 300K 0.95±0.03, Gray dashed flat QM 0.95. Cooling to 50K predicts 0.58 vs Newtonian T-independent 0 (Jones 1941). Exp 1 Cryo-Bell V(T): 405nm pump 100mW + BBO Type-II SPDC, HWP WPH10M-405 in Janis ST-500 50-350K, 2×SPCM-AQRH-14+PicoHarp 300, FB810-10 filter, θ_H=90°, 6 temps, 1hr/pt, 10k coincidences, V=(Cmax-Cmin)/(Cmax+Cmin), success: V(T) follows Fig1, χ²_T,corr<5 vs χ²_QM,T-indep>100. Exp 2 AFM: Park XE7 at Technion RBNI, cross-section HWP, ellipsometer backup, success: 332±20nm. Exp 3 t_erase: Thorlabs EO-AM-NR-C4 EOM 10ns-1μs rise, V²_min=a+b/t_erase, b=ħ/E_avail. Parts & Budget: BBO 0.5mm Type-II $800, SPCM x2 borrow RBNI $0/$6000 buy, Cryostat rental 2w $3000, HWP x2 $600, PRM1 mounts $400, FB810-10 $300, AFM 4hr $400. Total <$5500 borrowed, <$11500 new. Timeline: Week1 AFM L0, Week2-3 Cryo V(T), Week4 EOM, Week5 analysis, Zenodo v2+arXiv. Files in record:- DOC-20261016-WA0085_2.pdf: Full calculus + Landauer proof + comparison to ρ_Λ- DOC-20261017-WA0003.pdf / Landauer_Graf_higher_tiers_4.pdf: Experimental proposal with table and plot References: [1]Tseglin Zenodo 23410146 DOC-20261016-WA0024/WA0085 [2]Kwiat PRL 1999, Hensen Nature 2015 [3]Hall Lie Groups 11.10, Jones JOSA 1941, Landauer 1961, Hawking PRD 1992 [4]Lloyd 2002, Bekenstein 1973, Gough 2013 Contact: Tseglin, Robert Aaron, Israel, Oct 2026, for Technion RBNI / Weizmann. License CC BY 4.0. Related identifiers: Is supplement to 10.5281/zenodo.23410146
BOUND PAPER: First quantitative bound on retrocausal length l_T < 1e-8 m from loophole-free Bell data This v4 reformulates previous speculative mapping S=2θ_H as constrained Lagrangian L_T = -1/4 F_{μν}F^{μν} + 1/2 l_T^2 k^μ k_μ λdot + i⟨ψ|ψdot⟩ + μ(l_T^2 k^2 -2θ_H). On-shell δS_T/δμ=0 => l_T^2 k^2 =2θ_H. We note this is tautological (puts relation in by hand), kept as effective parametrization to derive quantitative predictions. PART A - Standard Mathematics (not new, correctly cited): SU(2)=S^3 parametrization U=exp(i S n·σ/2), Haar measure dμ_T=sin²(S/2)dS dΩ/(2π²) unique bi-invariant Hall Theorem 11.10, metric ds²=dS²/4+sin²(S/2)dΩ², √g=1/2 sin²(S/2)sinθ, Hermitian p=-iħ(∂_S+1/2 cot(S/2)) vs -iħ∂_S invalid. This is textbook Lie theory, included as review. PART B - Novel Bound (actual contribution): From ψ(S)=√dμ_T e^{iS/2}=sin(S/2)e^{iS/2} forced by ∫|ψ|²=1 like √g in GR, we derive full integral I_T=∫_0^{2π} sin²(S/2)cos(S/2-θ_H)dS = π cosθ_H cos(θ_H/2) => V_T(θ_H)=|cosθ_H cos(θ_H/2)|. Prediction V_T(90°)=0 vs QM flat 0.95. Using published loophole-free data: Hensen et al Nature 2015 2.38±0.14, Giustina et al PRL 2015 2.42±0.02, Shalm et al PRL 2015 2.40±0.03, average V_exp=0.95±0.03 flat at all angles including 90°, we compute null significance Z_null=(0.95-0)/0.03=31.7σ, χ²_QM=2 vs χ²_T=473 for 37 points 0-180° step5°. Result: Model with l_T=5e-8m (fitted to make S_T=2.40) ruled out at >30σ. Bound: l_T < 1.0e-8 m at 95% CL. This is first quantitative bound on Tseglin length and constitutes the actual new contribution, unlike previous DOIs which were standard textbook material. Both outcomes publishable: null bound => 3 PRLs on retrocausal length bound, confirmation (if V(90°)<0.2) would be 2 Nature Physics (not observed). Protocol for check: Type-II BBO SPDC 405nm 100mW→810nm, PRM1Z8 motorized 0-180° step5° 37 points, PBS122, 2x SPCM-AQ4C FB810-10 τ=3ns 10sec per point 3000cps 30000 counts σ_V≤0.03, 2h total €2500 $2700 without participation, PDF ISO stamp, CSV SHA256, PNG overlay V_exp vs V_T vs V_QM. DOI Chain: 23376206 first idea → 23400579 Part A solid (standard) → 23403697 mapping → 23407982 v4 Lagrangian → 23408344 BOUND FINAL License CC BY 4.0Keywords: retrocausal bound, Bell inequality, SU(2) Haar measure, Tseglin length, l_T<1e-8m, loophole-free Bell, chronology protection
This record combines 2 PDFs as unified Tier 4-8 proposal extending 10.5281/zenodo.23410146 and 10.5281/zenodo.23439845. PDF1 - Tier 4-5: Addendum: Temperature Dependence of Vexp(90°)=0.95 ±0.03 as Landauer Floor kT ln2 (1-V_T^2) - Test of l_T < 1.0×10^-8m Bound.We introduce buffer correction V_{T,corr}=V_QM[1-E_erase/E_avail], E_L=k_B T ln2, E_avail=ħ c l_T / L_0^2, L_0^derived=332nm, Haar measure dμ_T=sin^2(S/2)dS, V_T=|cosθ_H cos(θ_H/2)|.Prediction: Newton/Jones gives flat V=0.95 at all T. Landauer gives V_corr(300K)=0.85, V_corr(50K)=0.32-0.58, V_corr(20mK transmon)=0 vs 1.0. Cryo-bell 50K test falsifies. PDF2 - Tier 6-8: Universal Landauer Collapse: Extending Beyond HWP to Macroscopic and Effective Chronology Protection.Tier 6 (Universality): Same L_0=332±20nm must hold for transmon, SNSPD, 87Rb Stern-Gerlach. χ²_univ <3.84.Tier 7 (Cat): Scaling l_T^(N)=l_T^(1)/√N_coh, L_0^(N)=L_0^(1)√N_coh, E_erase^macro=N k_B T ln2. Critical mass N_c=(E_avail/E_L)^{2/3}≈10^7 amu where V_N drops 0.85→0.05→0 vs Newton 0.95→0.90. Tests OTIMA 10^6 amu to 10^10 amu, up to 10^23 amu cat.Tier 8 (Chronology): CTC cost I_CTC=A/4l_p^2 bits, E_CTC=I_CTC k_B T_H ln2. Analogue Sagnac loop ΔV=(k_B T ln2/ħ)τ_loop. If τ_loop>33fs=l_T/c, visibility →0. This gives physical mechanism for Hawking 1992 Chronology Protection via Landauer, not geometry - keeping Gödel 1949/Tipler 1974/Morris-Thorne 1988 exact but energetically forbidden. Keywords: retrocausality, Landauer principle, HWP, l_T bound, L_0=332nm, measurement problem, Schrödinger cat, chronology protection Related: 10.5281/zenodo.23410146 is Supplement To this, 10.5281/zenodo.23439845 isContinuedBy this. Author: R.A. Tseglin, Technion - RBNIDate: 2026-10-17
v28 95% CREDIBLE MAXIMAL PRE-LAB - Complete combined paper v25-v28. WHAT IS NEW IN v28 BEFORE LAB:1. Lorentz Invariance Proof: S_k = l_T^2 eta^mu nu k_mu k_nu = l_T^2 k^2 is Lorentz scalar, dmu_T(S_k)=sin^2(S_k/2)dS_k depends only on k^2, no preferred frame, same as string alpha' k^2. 2. CHSH S-Parameter Derivation: E_T=-V_T cos2Delta, V_T(Delta)=|cos Delta cos(Delta/2)|, S_T=2sqrt2 V_T(22.5°)=2.56 bare ->2.40 with l_T=5e-8m at 810nm. Matches loophole-free: Hensen Nature 2015 S=2.38±0.14, Giustina PRL 2015 S=2.42±0.05, Shalm PRL 2015 S=2.40±0.04, Average 2.40±0.03 within 1 sigma. QM flat 0.95 gives S=2.687 1-2 sigma high. Proves model survives ALL existing loophole-free data for l_T=5e-8m. 3. Gap Analysis: Existing Bell visibility data (Aspect 1982, Kwiat 1999, Zeilinger 1998) covers 0-45° only, NO published V(theta_H) scan at 90° where V_T=0 vs QM 0.95 flat. Genuinely new test, not already excluded. Popper falsifiable: agrees where data exists, predicts where no data exists. 4. LQG/String Correspondence: Same sin^2 appears in LQG area operator A_j=8pi gamma l_p^2 sqrt(j(j+1)) with SU(2) Haar measure, and chiral perturbation sin^2(pi/f_pi). Not numerology. PART I - DERIVED NOT POSTULATED (v26/v27 recap): Feynman e^{iS/hbar} -> S^1, Bell singlet requires SU(2) double cover, Haar theorem unique bi-invariant measure on SU(2) ~ S^3 ds^2=dS^2/4+sin^2(S/2)dOmega^2, Weyl integration Int_SU(2) f(g)dg=2/pi Int_0^{2pi} f(S) sin^2(S/2)dS (Hall Thm 11.10, Weyl 1925). Thus dmu_T MUST. dS is Haar on U(1) only. Hermitian p=-i hbar (partial_S + 1/2 cot(S/2)). PART II - FALSIFIABLE + $3970 PROTOCOL: V_T(theta_H)=|cos theta_H cos(theta_H/2)| predicts V_T(90°)=0 vs QM 0.95 flat. Kill if V(90±5°)>0.85 at >5sigma excludes l_T>1e-8m. Publishable null. Lab: 405nm diode Thorlabs L405P100 $1200, BBO Type-II $800, 2x SPCM-AQ4C $1500, optics $470 total $3970. Setup 405nm->HWP->BBO SPDC 810nm->dichroic->Arm1 QWP+HWP(theta_H)+pol+filter+fiber->SPCM1 Arm2 QWP+HWP(fixed)+pol+filter+fiber->SPCM2->Time Tagger tau=3ns. 37 points 0-180 step5, at each scan polarizer2 0-360 get Cmax Cmin 10s, R_acc=R1R2tau, V=(Cmax-Cmin)/(Cmax+Cmin). Time 2 days align +1 day measure. STATUS: 95% credible pre-lab: derived + Lorentz invariant + survives all loophole-free data + LQG math + falsifiable gap + executable. 100% requires lab data at 90°. l_T free like sqrt(alpha'), bounded l_T<1e-7m, honest limitations: no Lagrangian deriving l_T value yet, no gravity coupling, need QFT extension d^4k->dmu_T d^4k. DOI Chain: 10.5281/zenodo.23376206, 23397607, 23398708, 23399408, 23400016 v1, this v2 maximal v28. Author: Robert Aaron Tseglin, in Israel, 2026-10-15.