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The Effective Field F in the Decoherence Principle: From Local Interactions to Fractal Structures

Gennadirvich Andrey Ryabokon

Published Feb 18, 2026• 0 citations
Publisher

Abstract

This is the second paper in a series on the phenomenological principle of decoherence. The first paper, "Phenomenological Principle of Decoherence Based on the Integral Impact of Environmental Fields" (Ryabokon, 2026), is available at DOI: 10.5281/zenodo.18640591. In the present work, we elaborate on the physical meaning and possible realizations of the effective environmental field F(x), which plays a central role in the decoherence principle: C/C0 = exp(-α ∫_γ F²(x) dx). While the original formulation allowed F to represent any local interaction, here we show that in many realistic environments F is best described as a random field with fractal (scale-invariant) correlations. For such fields, the integral ∫ F² dx scales with the system size L as L^β, leading to a stretched-exponential decay of coherence: C/C0 = exp(-α' L^β). We derive the relation between the exponent β and the spectral index p of the field: β = p-2 (valid for 1 < p < 3). This result is supported by known examples from atmospheric optics (Kolmogorov turbulence, β = 5/3), biological tissues, and cosmological density fluctuations. We also discuss how to experimentally determine β and outline the limits of applicability of the proposed scaling. The framework does not modify the original principle but extends its domain to a broad class of natural and artificial media, offering a unified language for decoherence in complex environments.This publication is part of a broader conceptual program aimed at providing a unified phenomenological description of decoherence and attenuation processes. The framework is fully consistent with standard quantum mechanics and should be viewed as an organizing perspective rather than a proposal of new dynamics.

DOI
10.5281/zenodo.18677177

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Journal of Physics A Mathematical and General•Jan 19, 2004•64 citations
This is the second paper in a series on the phenomenological principle of decoherence. The first paper, "Phenomenological Principle of Decoherence Based on the Integral Impact of Environmental Fields" (Ryabokon, 2026), is available at DOI: 10.5281/zenodo.18640591. In the present work, we elaborate on the physical meaning and possible realizations of the effective environmental field F(x), which plays a central role in the decoherence principle: C/C0 = exp(-α ∫_γ F²(x) dx). While the original formulation allowed F to represent any local interaction, here we show that in many realistic environments F is best described as a random field with fractal (scale-invariant) correlations. For such fields, the integral ∫ F² dx scales with the system size L as L^β, leading to a stretched-exponential decay of coherence: C/C0 = exp(-α' L^β). We derive the relation between the exponent β and the spectral index p of the field: β = p-2 (valid for 1 < p < 3). This result is supported by known examples from atmospheric optics (Kolmogorov turbulence, β = 5/3), biological tissues, and cosmological density fluctuations. We also discuss how to experimentally determine β and outline the limits of applicability of the proposed scaling. The framework does not modify the original principle but extends its domain to a broad class of natural and artificial media, offering a unified language for decoherence in complex environments.This publication is part of a broader conceptual program aimed at providing a unified phenomenological description of decoherence and attenuation processes. The framework is fully consistent with standard quantum mechanics and should be viewed as an organizing perspective rather than a proposal of new dynamics.
The phenomenological decoherence principle introduced in Ryabokon (2026a) expresses coherence loss as an exponential of the integral of the squared effective field F. In this paper we analyze the statistical foundations of stretched-exponential decay, which arises when F possesses scale-invariant (fractal) statistics. Starting from a power-law spectrum Φ(k) ∝ k^{-p}, we derive explicit relations between the spectral index p and the stretched-exponential exponent β. For Gaussian fluctuations we obtain: β = p-1 for the field itself, and β = p-2 for integrated quantities (e.g., wave phase). The domain of validity and the role of non-Gaussian statistics are discussed. This publication is part of a broader conceptual program aimed at providing a unified phenomenological description of decoherence and attenuation processes. The framework is fully consistent with standard quantum mechanics and should be viewed as an organizing perspective rather than a proposal of new dynamics.
This work proposes a phenomenological formulation of a decoherence principle that relates the degree of suppression of quantum coherence to the integral of the squared effective environmental field in the physical systems and experimental configurations analyzed in this paper. The environment is treated as a set of effective physical influences relevant to a specific experimental or physical configuration and acting on the system. The applicability of the proposed principle is analyzed using seventeen experiments and observations spanning microscopic, mesoscopic, macroscopic, and cosmological scales. Seven key experiments are analyzed quantitatively and in detail, while the remaining ones are presented as supporting the broad applicability of the proposed phenomenological approach. This publication is part of a broader conceptual program aimed at providing a unified phenomenological description of decoherence and attenuation processes. The framework is fully consistent with standard quantum mechanics and should be viewed as an organizing perspective rather than a proposal of new dynamics.
This work introduces a minimal and operational framework for describing decoherence in open quantum systems as a finite-time process. Rather than proposing a new dynamical theory or modifying the axioms of quantum mechanics, the article introduces a bounded, causal, and dimensionless scalar quantity — a local temporal coherence field C(x,t), designed to diagnose the persistence of temporal correlations over a finite causal window. The coherence field is constructed from experimentally accessible observables or reduced-state quantities via a kernel-weighted causal average. It does not represent a new physical degree of freedom and does not introduce additional equations of motion. Instead, it provides a compact diagnostic layer that makes the finite-time structure of coherence explicit, complementing standard descriptions based on memory kernels, time-dependent generators, and Lindblad master equations. The framework is shown to interface naturally with non-Markovian dynamics, coherence-weighted decoherence processes, and effective decay rates, while remaining consistent with standard GKSL structures in the appropriate limits. Its scope, limitations, and relation to existing non-Markovianity measures are explicitly discussed. The coherence-field perspective is intended as an operational and experimentally falsifiable diagnostic tool, applicable across a range of contemporary platforms where finite-time coherence effects are relevant (e.g. superconducting circuits, hybrid light–matter systems, and driven non-equilibrium regimes).This article forms part of the broader Ranesis conceptual framework, which investigates the role of finite-time persistence, coherence, and temporal organization across physical and informational systems. Within that context, the present work constitutes a self-contained and domain-specific application to open quantum systems. No assumptions, postulates, or formal structures from the broader framework are required to read or validate the results presented here.
Quantum decoherence is conventionally understood as an environment-induced loss of phase coherence, described operationally through reduced density matrices and effective noise models. While this framework successfully captures how decoherence occurs, it leaves open the deeper physical question of why quantum phase coherence is generically fragile and lacks intrinsic protection. In this work, we propose a reinterpretation of decoherence within the Temporal Theory of the Universe (TTU), where time is treated as a physical field rather than an external parameter. We argue that decoherence can be understood as a manifestation of temporal-field inhomogeneity: a breakdown of global phase synchronization caused by spatial and temporal gradients of the underlying time field. Within this perspective, environmental noise and non-Markovian effects emerge as effective descriptions of deeper temporal misalignment rather than fundamental sources of randomness. We demonstrate how temporal-field inhomogeneity naturally induces phase damping in the reduced density matrix, leading to decoherence without invoking irreversible information loss. The framework remains fully compatible with standard quantum mechanics at the operational level, while offering a novel physical substrate for coherence, noise, and temporal memory effects. Finally, we outline several experimentally discriminable consequences of this interpretation, positioning it as a falsifiable and conceptually economical extension of existing decoherence theory. Keywords: quantum decoherence; temporal field; foundations of quantum mechanics; open quantum systems; phase coherence; density matrix; Lindblad master equation; non-Markovian dynamics; time as a physical field; quantum foundations. 1.Introduction 1.1.The decoherence problem as a foundational issue in quantum theory 1.2.Standard environmental and information-theoretic interpretations 1.3.Motivation for an alternative physical substrate 1.4.Scope and limits of the present work (interpretational, not engineering) 2. Decoherence in Standard Quantum Theory 2.1 Density matrix formulation and phase damping 2.2 Environment-induced decoherence and pointer states 2.3 Markovian vs non-Markovian regimes 2.4 Conceptual gap: why phase coherence is generically fragile Key point: standard theory describes how decoherence happens, but not why phase coherence lacks physical protection. 3. Temporal Field Framework (TTU Perspective) 3.1 Time as a physical field τ(x) rather than a parameter 3.2 Local temporal gradients and phase evolution 3.3 Global time-phase coherence as a physical condition 3.4 Relation to hyper-time / meta-time extensions (conceptual overview) 4. Reinterpreting Decoherence as Temporal-Field Misalignment 4.1 Phase evolution in inhomogeneous temporal backgrounds 4.2 Decoherence as loss of global time-phase synchronization 4.3 Effective noise as manifestation of temporal-field fluctuations 4.4 Comparison with environmental noise models Central thesis: Decoherence reflects not fundamental randomness, but breakdown of coherent phase evolution due to temporal-field inhomogeneity. 5. Relation to Known Quantum Phenomena 5.1 Non-Markovian dynamics as temporal memory effects 5.2 1/f noise and slow temporal drift 5.3 Temporal entanglement and time-correlated errors 5.4 Distinction from collapse models and hidden variables 6. Conceptual Advantages of the Temporal-Field Interpretation 6.1.Physical substrate for phase coherence 6.2.Natural explanation of environment sensitivity 6.3.Unified language for decoherence, noise, and drift 6.4.Compatibility with standard quantum formalism 7. Testable Consequences and Falsifiable Signatures 7.1.Test 1 — Temporal Gradient Sensitivity 7.2.Test 2 — Non-Markovian Residual Structure 7.3.Test 3 — Global Synchronization Effects 8. Limitations and Open Questions 8.1.No claim of immediate technological implementation 8.2.No replacement of quantum error correction 8.3.Relation to gravity and cosmology remains theoretical 8.4.Need for independent experimental discrimination 9. Discussion 9.1.Positioning relative to mainstream decoherence theory 9.2.Relation to other time-based approaches 9.3.Why temporal ontology matters for quantum foundations 10. Conclusion 10.1.Summary of reinterpretation 10.2.Why this framework is explanatory rather than speculative 10.3. Outlook for foundational and experimental research Reference Appendix A: Dimensional and Conceptual Consistency Check
Based on the superposition principle, any two states of a quantum system may be coherently superposed to yield a novel state. Such a simple construction is at the heart of genuinely quantum phenomena such as interference of massive particles or quantum entanglement. Yet, these superpositions are susceptible to environmental influences, eventually leading to a complete disappearance of the system's quantum character. In principle, two distinct mechanisms responsible for this process of decoherence may be identified. In a classical decoherence setting, on the one hand, stochastic fluctuations of classical, ambient fields are the relevant source. This approach leads to a formulation in terms of stochastic Hamiltonians; the dynamics is unitary, yet stochastic. In a quantum decoherence scenario, on the other hand, the system is described in the language of open quantum systems. Here, the environmental degrees of freedom are to be treated quantum mechanically, too. The loss of coherence is then a direct consequence of growing correlations between system and environment. The purpose of the present thesis is to clarify the distinction between classical and quantum decoherence. It is known that there exist decoherence processes that are not reconcilable with the classical approach. We deem it desirable to have a simple, feasible model at hand of which it is known that it cannot be understood in terms of fluctuating fields. Indeed, we find such an example of true quantum decoherence. The calculation of the norm distance to the convex set of classical dynamics allows for a quantitative assessment of the results. In order to incorporate genuine irreversibility, we extend the original toy model by an additional bath. Here, the fragility of the true quantum nature of the dynamics under increasing coupling strength is evident. The geometric character of our findings offers remarkable insights into the geometry of the set of non-classical decoherence maps. We give a very intuitive geometrical measure---a volume---for the quantumness of dynamics. This enables us to identify the decoherence process of maximum quantumness, that is, having maximal distance to the convex set of dynamics consistent with the stochastic, classical approach. In addition, we observe a distinct correlation between the decoherence potential of a given dynamics and its achievable quantumness. In a last step, we study the notion of quantum decoherence in the context of a bipartite system which couples locally to the subsystems' respective environments. A simple argument shows that in the case of a separable environment the resulting dynamics is of classical nature. Based on a realistic experiment, we analyze the impact of entanglement between the local environments on the nature of the dynamics. Interestingly, despite the variety of entangled environmental states scrutinized, no single instance of true quantum decoherence is encountered. In part, the identification of the classical nature relies on numerical schemes. However, for a large class of dynamics, we are able to exclude analytically the true quantum nature.
In the last decade decoherence has become a very popular topic mainly due to the progress in experimental techniques which allow monitoring of the process of decoherence for single microscopic or mesoscopic systems. The other motivation is the rapid development of quantum information and quantum computation theory where decoherence is the main obstacle in the implementation of bold theoretical ideas. All that makes the second improved and extended edition of this book very timely. Despite the enormous efforts of many authors decoherence with its consequences still remains a rather controversial subject. It touches on, namely, the notoriously confusing issues of quantum measurement theory and interpretation of quantum mechanics. The existence of different points of view is reflected by the structure and content of the book. The first three authors (Joos, Zeh and Kiefer) accept the standard formalism of quantum mechanics but seem to reject orthodox Copenhagen interpretation, Giulini and Kupsch stick to both while Stamatescu discusses models which go beyond the standard quantum theory. Fortunately, most of the presented results are independent of the interpretation and the mathematical formalism is common for the (meta)physically different approaches. After a short introduction by Joos followed by a more detailed review of the basic concepts by Zeh, chapter 3 (the longest chapter) by Joos is devoted to the environmental decoherence. Here the author considers mostly rather `down to earth' and well-motivated mechanisms of decoherence through collisions with atoms or molecules and the processes of emission, absorption and scattering of photons. The issues of decoherence induced superselection rules and localization of objects including the possible explanation of the molecular structure are discussed in details. Many other topics are also reviewed in this chapter, e.g., the so-called Zeno effect, relationships between quantum chaos and decoherence, the role of decoherence in quantum information processing and even decoherence in the brain. The next chapter, written by Kiefer, is devoted to decoherence in quantum field theory and quantum gravity which is a much more speculative and less explored topic. Two complementary aspects are studied in this approach: decoherence of particle states by the quantum fields and decoherence of field states by the particles. Cosmological issues related to decoherence are discussed, not only within the standard Friedmann cosmology, but also using the elements of the theory of black holes, wormholes and strings. The relations between the formalism of consistent histories defined in terms of decoherence functionals and the environmental decoherence are discussed in chapter 5, also written by Kiefer. The Feynman--Vernon influence functional for the quantum open system is presented in detail as the first example of decoherence functional. Then the general theory is outlined together with possible interpretations including cosmological aspects. The next chapter by Giulini presents an overview of the superselection rules arising from physical symmetries and gauge transformations both for nonrelativistic quantum mechanics and quantum field theory. Critical discussion of kinematical superselection rules versus dynamical ones is illustrated by numerous examples like Galilei invariant quantum mechanics, quantum electrodynamics and quantum gravity. The introduction to the theory of quantum open systems and its applications to decoherence models is given in chapter 7 by Kupsch. Generalized master equations, Markovian approximation and a few Hamiltonian models relevant for decoherence are discussed. Some mathematical tools, e.g., complete positivity and entropy inequalities are also presented. The last chapter by Stamatescu is devoted to stochastic collapse models which can be interpreted either as certain representations of the dynamics of open quantum systems or as fundamental modifications of the Schr\"odinger equation. The final part of the book consists of remarks by Zeh on related concepts and methods and seven appendices. The broad spectrum, mathematically-friendly presentation, inclusion of the very recent developments and the extensive bibliography (about 550 references) make this book a valuable reference for all researchers, graduate and PhD students interested in the foundations of quantum mechanics, quantum open systems and quantum information. The relative independence of the chapters and numerous redundancies allow for selective reading, which is very helpful for newcomers to this field.