One FIN Operator, Two Temporal Dynamics: Unitary Propagation, Reversible Diffusion, a Finite Double-Slit Experiment, and Operational Completion
Krzysztof Żuchowski
Abstract
## Record metadata - **Title:** One FIN Operator, Two Temporal Dynamics: Unitary Propagation, Reversible Diffusion, a Finite Double-Slit Experiment, and Operational Completion- **Creator:** Żuchowski, Krzysztof- **Affiliation:** Independent Researcher — Fractal Information Theory Project- **ORCID:** 0009-0002-0909-3613- **Resource type:** Publication — Preprint - **Version:** 1.0.0- **Publication date:** 2026-07-19- **Language:** English- **Publisher:** Zenodo- **Access:** Open access, subject to the license confirmation below- **Reserved DOI:** [10.5281/zenodo.21435332](https://doi.org/10.5281/zenodo.21435332) ## Abstract This technical note studies a precisely defined twelve-site FIN matrix and the two canonical temporal calculi generated by its weighted graph Laplacian. Let (W) be the zero-diagonal real symmetric cyclic-distance matrix on (mathbb Z_{12}) sampled from \[K(d)=\frac{\cos(0.18575d+0.16250)}{1+d^{1.8}},\] using cyclic distances (d=1,ldots,6). Its common row sum is \[s=1.660307278766099\] to fifteen decimal places, and \[A=sI-W.\] All off-diagonal weights used at (N=12) are positive. Therefore (A) is a connected weighted graph Laplacian and \[\langle f,Af\rangle=\frac12\sum_{x,y}W_{xy}|f_x-f_y|^2\ge 0.\] The same positive self-adjoint operator generates the unitary group \[U_t=e^{-itA}\] and the irreducible, symmetric, uniform-reversible Markov semigroup \[P_t=e^{-tA}.\] Although the two evolutions share Fourier eigenvectors and eigenvalues, their operational predictions are inequivalent. Markov diffusion has linear short-time escape, exact Chapman–Kolmogorov composition and exponential relaxation to the uniform law. Unitary position probabilities have quadratic short-time escape, interference, failure of population-level Chapman–Kolmogorov composition and no pointwise equilibrium. The release includes a reproducible finite double-slit analogue. A coherent preparation at vertices (-2) and (+2) is compared with a perfectly distinguishing which-path record and with classical diffusion. The interference term is displayed across all twelve detectors and through time. At the first local maximum of total interference, (t_*=1.5525), the symmetry detector has unit ideal visibility; reducing the overlap of the two environment/apparatus records continuously suppresses the fringe. The note also identifies the missing structure needed to convert the operator into an experimental model. The smallest established-style candidate is a **calibrated process–tester model**: a causal process tensor (quantum comb), an admissible tester containing preparations and instruments with classical records, and a clock/reference calibration. This object carries state, multitime dynamics, preparation, instruments, environmental memory, apparatus and records up to operational equivalence. The operator alone does not select a physical clock, dimensional scale, environment, apparatus, Born rule, orientation or temporal semantics. No cosmological, Theory-of-Everything or continuum-physics claim is made. ## Plain-language significance One finite operator can generate both wave-like and diffusion-like mathematics. That fact does not mean an observer turns one physical law into another. It means the static operator underdetermines the experiment. State preparation, phase reference, clock, environment, measurement instrument and stored record must be supplied before either family becomes a testable physical model. The included double-slit analogue makes the distinction visible: coherent alternatives interfere; a which-path record removes the cross term; classical diffusion produces a different distribution. These are three operational protocols built around the same finite matrix. ## Main results and confidence labels ### Proven - (A=sI-W) is positive semidefinite with (ker A=\operatorname{span}\{\mathbf 1\}) under the declared cyclic-distance convention.- The spectral gap is (0.754121154207080) to displayed precision.- (U_t=e^{-itA}) is unitary.- (P_t=e^{-tA}) is an entrywise positive, symmetric, doubly stochastic Markov semigroup for (t>0).- The scalar shift (s) is the unique scalar shift of this regular (W) that makes (A\mathbf1=0).- Born-position matrices (|U_t|^{\circ2}) do not form a nontrivial differentiable Markov semigroup.- No nontrivial continuous finite evolution can be both unitary and entrywise nonnegative stochastic.- The two-slit probability law follows from the stated coherent preparation, record overlap and detector POVM.- A dimensionful time, energy, mass, length or action scale cannot be selected from the dimensionless matrix alone. ### Computed and independently checkable - All six weights, the complete spectrum, the spectral gap and the Dirichlet-form residual.- Markov mixing times and the nonuniform unitary Cesàro position law.- Unitarity, stochasticity and Chapman–Kolmogorov residuals.- The first two-slit interference maximum (t_*=1.5525) and total-variation interference (0.1232806696).- Ideal phase-fringe visibility (1) at detector (x=0) for record overlap (eta=1). ### Candidate / strong structural evidence - A calibrated process–tester model is the smallest standard mathematical structure found that simultaneously carries the requested operational roles. ### Not established - That the FIN matrix is a measured Hamiltonian or measured stochastic generator.- That unitary or diffusive time is selected by FIN itself.- That the displayed parameter (t) is measured in seconds.- That Shannon entropy in the plots is thermodynamic entropy.- That the (N=12) Markov interpretation survives a continuum limit.- That a microscopic apparatus, environment, selector, orientation or physical constants are derived from (A). ## Double-slit simulation The simulated slit modes are (a=10\equiv-2\pmod{12}) and (b=2). The coherent system–record state is \[|\Psi_\phi\rangle=\frac{|a\rangle|E_a\rangle+e^{i\phi}|b\rangle|E_b\rangle}{\sqrt2},\qquad \eta=\langle E_b|E_a\rangle.\] With (u_j(x,t)=\langle x|U_t|j\rangle), the detector law is \[p_{\phi,\eta}(x,t)=\frac{|u_a|^2+|u_b|^2}{2}+\operatorname{Re}\!\left(\eta e^{-i\phi}u_a\overline{u_b}\right).\] The figure compares: 1. coherent propagation, (eta=1);2. a which-path record / incoherent mixture, (eta=0);3. classical diffusion (P_t(\delta_a+\delta_b)/2). This is a finite two-path interferometer on (mathbb Z_{12}), not a continuum optical diffraction calculation. ## Important finite-size limitation The Markov conclusion uses positivity of all off-diagonal weights present at (N=12). The fixed profile becomes negative at distance (8): \[K(8)=-0.0017958784.\] A naive cyclic extension first includes that distance at (N=16), where the resulting off-diagonal matrix entry cannot be a Markov jump rate. Any truncation, rectification, absolute-value prescription or parameter running would be an additional axiom. The release therefore makes an exact (N=12) claim and no automatic continuum-limit claim. ## Files in this release | File | Purpose | SHA-256 ||---|---|---|| `FIN_Dual_Dynamics_Operational_Completion.pdf` | Archival English research note | `53bad7dfc10446211d9bc6bc28da53470ee3e46b4b4084d23f2301a439f2456c` || `FIN_Dual_Dynamics_Operational_Completion.tex` | LaTeX source | `be38e241f3b4b7ba73230845cc584806c1b5102c18de6dbcc1dde0818b614765` || `fin_dual_dynamics_release.py` | Deterministic numerical audit and figure generator | `671dca9f2ac0b40f17bad3cda8e253e934db825503f76e1efa787b47c262ad47` || `FIN_Dual_Dynamics_reference_results.json` | Machine-readable expected results | `3917ad393abe286d1f39caeac6596d218b56b369cffdfe405a3aa6f79156e5ab` || `FIN_One_Spectrum_Two_Dynamics.png` | Unitary/Markov comparison figure | `5e37f1ff1e49cce4855247c03f4bd298ade73e3da1ecd4136ad77875c43d2f42` || `FIN_Double_Slit_Operational_Simulation.png` | Four-panel double-slit simulation | `a6a1f59b9c6d5b4df17df6580679b18f9706421ca5a0aedeb916da84ac27488d` || `FIN_Dual_Dynamics_MANIFEST.sha256` | Checksums for the archival files | Generated after the final build | The Markdown release description is intentionally omitted from its own checksum table to avoid a self-referential digest. ## Reproducibility Reference environment used for this release: - Linux 7.0.0-28-generic, x86_64- Python 3.12.3- NumPy 1.26.4- Matplotlib 3.10.8- pdfTeX 3.141592653-2.6-1.40.25 / TeX Live 2023- Floating-point arithmetic: IEEE-754 binary64- Random seed used only for the Dirichlet identity spot-check: `20260719` Run: ```bashpython3 fin_dual_dynamics_release.pypdflatex -interaction=nonstopmode -halt-on-error FIN_Dual_Dynamics_Operational_Completion.texpdflatex -interaction=nonstopmode -halt-on-error FIN_Dual_Dynamics_Operational_Completion.tex``` The script reconstructs the operator from the displayed analytic parameters, generates both figures and writes the complete numerical audit to JSON. It tests symmetry, the constant mode, Dirichlet positivity, unitarity, stochasticity, minimum transition entries, Chapman–Kolmogorov composition, mixing, the raw-(W) heat failure, the first negative extended-profile weight and normalization of all double-slit distributions. ## Keywords FIN kernel; spectral operator; weighted graph Laplacian; unitary group; heat semigroup; reversible Markov chain; continuous-time quantum walk; double-slit interference; which-path information; decoherence; quantum instrument; process tensor; quantum comb; calibrated process–tester model; observer dependence; operational equivalence; finite operator theory; spectral dynamics. ## Suggested citation > Żuchowski, K. (2026). *One FIN Operator, Two Temporal Dynamics: Unitary Propagation, Reversible Diffusion, a Finite Double-Slit Experiment, and Operational Completion* (Version 1.0.0) [Technical note]. Zenodo. https://doi.org/10.5281/zenodo.21435332 ```bibtex@misc{zuchowski_fin_dual_dynamics_2026, author = {Krzysztof Żuchowski}, title = {One FIN Operator, Two Temporal Dynamics: Unitary Pro