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Dual-Axis Entropy Production and the Recovery of Classical Thermodynamics: A Physical–Observation Formulation

Xianwei Meng

Published Oct 4, 2026• 0 citations
Publisher

Abstract

Physical–Observation Dual-Axis (PODA) theory retains the physical state and the objective state of record formation as distinct responsibilities. We develop a thermodynamic formulation on their admissible joint histories, starting from a common energy, an explicitly specified thermal closure and a declared physical time reversal. For a finite-state realization with channel-resolved local detailed balance, the full trajectory entropy production obeys the usual integral fluctuation relation. We prove an exact decomposition of its mean into the relative entropy visible in a declared record and a nonnegative conditional contribution from the unrecorded joint history. Equality holds precisely when the forward and reverse conditional history laws coincide. An exact recovery theorem identifies preservation of the observation section, marked history laws, energy exchanges and reverse protocol. A separate sufficiency criterion determines whether a record captures all entropy production. The finite-state section recovers the first and second laws, Gibbs equilibrium and isothermal free-energy dissipation of the reduced system. Two analytic models distinguish correlation loss from heat release and demonstrate positive joint entropy production with stationary equilibrium marginals. A regular perturbation formula expresses the leading hidden entropy production through conditional score mismatch. The results give conditional, exact criteria for thermodynamic recovery within PODA and identify the dynamical quantities required for departures from a fixed observation description.

DOI
10.20944/preprints202610.0168.v1

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•Jul 13, 2011•2 citations
Physical–Observation Dual-Axis (PODA) theory retains the physical state and the objective state of record formation as distinct responsibilities. We develop a thermodynamic formulation on their admissible joint histories, starting from a common energy, an explicitly specified thermal closure and a declared physical time reversal. For a finite-state realization with channel-resolved local detailed balance, the full trajectory entropy production obeys the usual integral fluctuation relation. We prove an exact decomposition of its mean into the relative entropy visible in a declared record and a nonnegative conditional contribution from the unrecorded joint history. Equality holds precisely when the forward and reverse conditional history laws coincide. An exact recovery theorem identifies preservation of the observation section, marked history laws, energy exchanges and reverse protocol. A separate sufficiency criterion determines whether a record captures all entropy production. The finite-state section recovers the first and second laws, Gibbs equilibrium and isothermal free-energy dissipation of the reduced system. Two analytic models distinguish correlation loss from heat release and demonstrate positive joint entropy production with stationary equilibrium marginals. A regular perturbation formula expresses the leading hidden entropy production through conditional score mismatch. The results give conditional, exact criteria for thermodynamic recovery within PODA and identify the dynamical quantities required for departures from a fixed observation description.
Observer-information entropy production quantifies the loss of recoverable information about a physical source when an already formed observation undergoes source-independent irreversible degradation. The statistical second-law statement Σobs[s,t]=I(X;Rs)−I(X;Rt)=I(X;Rs∣Rt)≥0 \Sigma_{\mathrm{obs}}[s,t] =I(X;R_s)-I(X;R_t) =I(X;R_s\mid R_t)\ge 0 Σobs​[s,t]=I(X;Rs​)−I(X;Rt​)=I(X;Rs​∣Rt​)≥0 follows from data processing, but by itself it does not identify a physical energetic or thermodynamic cost. This paper establishes such a connection within an explicit and deliberately restricted stochastic-thermodynamic regime. We consider a finite observer memory RtR_tRt​ coupled to a single heat bath at temperature TTT. A source label XXX is fixed during the passive relaxation, the transition generator of RtR_tRt​ is independent of XXX, and the memory dynamics satisfies detailed balance with respect to a strictly positive equilibrium law qqq. For the joint source--memory ensemble and for the unconditioned memory marginal, we define the standard stochastic-thermodynamic entropy-production rates. Using the relative-entropy chain rule and the detailed-balance HHH-theorem, we prove the exact correlation-dissipation decomposition S˙totXRkB=σobs+S˙totRkB. \frac{\dot S_{\mathrm{tot}}^{XR}}{k_B} = \sigma_{\mathrm{obs}} + \frac{\dot S_{\mathrm{tot}}^{R}}{k_B}. kB​S˙totXR​​=σobs​+kB​S˙totR​​. Consequently, S˙totXR≥kBσobs,ΔStotXR[s,t]≥kBΣobs[s,t]. \dot S_{\mathrm{tot}}^{XR}\ge k_B\sigma_{\mathrm{obs}}, \qquad \Delta S_{\mathrm{tot}}^{XR}[s,t]\ge k_B\Sigma_{\mathrm{obs}}[s,t]. S˙totXR​≥kB​σobs​,ΔStotXR​[s,t]≥kB​Σobs​[s,t]. At fixed temperature the same result is an excess-free-energy dissipation bound, \[ \Fex_{XR}(s)-\Fex_{XR}(t) \ge k_BT\Sigma_{\mathrm{obs}}[s,t]. \] Equality holds when the memory marginal remains at equilibrium, in which case all thermodynamic irreversibility is attributable to the destruction of source--record correlation. A symmetric two-state memory provides an exactly solvable saturation example. The result is not a universal Landauer principle. It constrains total entropy production and loss of nonequilibrium free energy during passive decorrelation; it does not assert a universal heat or work cost for arbitrary information loss. Driven memories, source-dependent transition rates, active measurement, feedback, multiple reservoirs, and nonequilibrium steady states require the broader information-thermodynamic bookkeeping developed in stochastic thermodynamics. We then place the thermodynamic result beside two Fisher--Shannon bridges. Under Gaussian observation heat flow Yt=X+BtY_t=X+B_tYt​=X+Bt​, observer-information dissipation obeys the exact identity σobs(t)=12(dt−J(Yt))=12t2mmse⁡(X∣Yt), \sigma_{\mathrm{obs}}(t) = \frac12\left(\frac{d}{t}-J(Y_t)\right) = \frac{1}{2t^2}\operatorname{mmse}(X\mid Y_t), σobs​(t)=21​(td​−J(Yt​))=2t21​mmse(X∣Yt​), while pairwise statistical distinguishability obeys \[ \frac{d}{dt}\KL(p_t\|q_t) =-\frac12\Jrel(p_t\|q_t). \] Recent temporal-Fisher speed-limit results provide a complementary route from physical entropy production to the speed of probability evolution. Together these results separate three objects that are often conflated: thermodynamic irreversibility, Shannon information loss about the physical source, and Fisher-geometric statistical motion. The paper thereby supplies a physical-cost layer for observer information theory without identifying information with energy or thermodynamic entropy.
When the conditions under which a record is formed remain fixed, a physical theory may represent that record completely by a unary law of the state observed. This paper asks what structure is forced when the same independently certified physical identity gives different complete records under different formation conditions. The initial datum distinguishes two typed empirical roles, while the state identity of the formation side is derived from its complete behavior. Failure of factorization through the first projection proves that the formation-side role cannot be deleted. The complete row and column behaviors of the primitive law then determine two kernel pairs and their coequalizers. Unique descent retains every observable distinction while removing every redundant label, and the resulting realization is terminal among all exact role-preserving realizations. The product pairs the reduced roles; a pullback extracts the combinations on which records can actually be formed. Only after these steps does exponential transposition identify each surviving formation class with one complete response map. The resulting bijection supplies the state criterion and establishes the observation-state object. Compatibility with the antecedent theory preserves the independently given physical state space and yields the physical–observation law in which a fact is generated jointly by the state observed and the state of observation. The same construction gives exact criteria for conditional, label-free, and joint identifiability and selects the same-source pullback on which transport may subsequently be defined. A nonzero coherent response on that pullback yields the phase-transport fundamental equation, the first fundamental equation written directly on observation space. Quantum theory subsequently enriches this canonical interface. Coherent response and full circular phase select the complex field; reversible binary mixing yields CP1 ∼= S2 ; independent composition creates the four-dimensional event domain; response-event identity glues probabilities across complete contexts; and Gleason representation with marginal consistency gives the Born trace pairing. The two-qubit correlation tensor then yields the singlet cosine law, the CHSH inequality, the Tsirelson bound, and the Horodecki spectral criterion. Bell violation is thereby identified with the absence of a positive global answer section across incompatible observation states. The quantum formalism is thereby closed into one architecture: complex state geometry describes coherent physical possibility, complete observation states specify the ways in which facts may form, the Born interface joins them, and quantum instruments carry a realized fact into subsequent dynamics. Fixed observation sections recover classical unary laws, while smooth equivariant enrichment lifts relativistic frame geometry and internal gauge geometry to the same joint domain. The central result is ontological. Physobser Theory admits observation into objective physical reality not as a mind, an external readout, or a perturbation, but as an irreducible state-bearing axis; a fact is generated at its lawful interface with physical state. Category theory is the proof instrument. The discovered physical content is the dual-axis constitution of facts, which supplies a common foundation for quantum, classical, relativistic, and gauge physics.
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Problem What must a physical record preserve to reveal temporal direction, measure duration, and support a calibrated experiment? This two-volume mathematical working paper distinguishes causal order, clock readings, and forward–reverse evidence, and studies their joint realization under one history law. Principal results Relative-entropy disintegration identifies evidence lost through observation. Graph potentials characterize sufficient current sensors by the absence of affinity on unobserved cycles; paired histories extend the criterion to silent events and indistinguishable reaction channels. Anonymous records, finite memory, and stopped decisions are treated explicitly. Compensated currents control clock calibration under shared environmental dynamics. A preparation-and-work identity bounds directional records and terminal organization together. Exact elimination retains hidden memory, while inverse and energy margins control response. A moving-sector comparison bounds the complete quantum apparatus record, including interactions, leakage, and transport; a spectral gap gives an explicit operating-time estimate. Analytical constructions and counterexamples cover graph–matter selection, ring and torus persistence, localized field clocks and receivers, and source-correlated records. A kinetic parent combines a selected ring, an inertial field, and a finite reversible receiver. Preparation frontiers separate information cost from attainable initial laws of a fixed dynamics. Methods, scope, and open questions The proofs use conditioning, path potentials, martingale compensation, generating functions, and stable operator comparison. The project includes editable sources, bibliography, 47 reproducible finite verification programs, provenance, and a separate corrections report. The results concern specified model classes and conditional external inputs. Selected spatial geometry is not a derived Lorentzian spacetime; the joint ring receiver uses supplied capture materials and diffusive transport. A common microscopic derivation of Lorentzian geometry, apparatus formation, two distinct proper-time clocks, constrained gravitational response, and typical directional preparation remains open.
Thermodynamics is a phenomenological theory describing the energy conversion of work and heat. At its origins thermodynamics was developed in order to understand and improve heat engines. In conventional thermodynamics, however, only such processes are completely describable which are slow enough to keep the system of interest in an equilibrium state with its thermal environment at all times. On the contrary, all real physical processes are accompanied by non-equilibrium phenomena. These are mathematically described with the help of the irreversible entropy production, i.e. the dissipated work divided by the temperature of the bath. The second law of thermodynamics merely states that the irreversible entropy production is on average always positive. The modern trend of miniaturization, however, leads to smaller and smaller devices. On short length scales thermal noise as well as quantum fluctuations become important. Thus, usual thermodynamic quantities as work and heat acquire stochastic nature. Moreover, in the quantum regime a completely new theory had to be invented, since classical notions of work and heat are no longer valid. The present dissertation contributes to this prevailing field by the derivation of analytical expressions for the entropy production in open and closed quantum system far from thermal equilibrium. The theoretical treatment is motivated by an experimental point of view. The obtained results were derived from the reduced dynamics of the quantum mechanical system, which may be coupled to a thermal bath. To this end, it was dealt with methods and approaches of statistical physics, conventional thermodynamics, quantum information theory and the theory of open quantum systems. In this dissertation the most important physical systems are treated. First, an isolated system is considered before later on a heat bath is included. The limit of weak as well as of strong coupling are analyzed in detail. For isolated systems it turns out that a geometric approach is able to capture the thermodynamic properties, completely. To this end, the irreversible entropy production is sharply estimated from below by the angle between the real non-equilibrium state and the corresponding equilibrium one. Further, it is shown that the Heisenberg uncertainty relation for energy and time can be formulated more precisely in terms of that angle. As experimental system cold ion traps are introduced, in which the theoretical predictions can be verified. For weakly coupled systems, then, the irreversible entropy production is identified and a fluctuation theorem is derived by merely thermodynamic arguments. As experimental system we, again, propose the cold ion traps, where the heat bath can be simulated with the help of LASER light. In the limit of strong coupling a semiclassical description of the reduced quantum system is discussed. Again, an analytically exact expression for the entropy production and the corresponding fluctuation theorem is derived. A physical system, in which strong coupling to the environment can be analyzed, is given by Josephson junctions. This dissertation discusses the entropy production for isolated, weakly coupled, and overdamped quantum systems. For these physical regimes analytical relation are derived and experimental systems proposed, with which the predictions can be verified.