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Acta Physica Academiae Scientiarum Hungaricae

Entropic changes in a measured quantum-mechanical object

Vladimír Majerník

Published Dec 1, 1971• 0 citations
Publisher
DOI
10.1007/bf03157086

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Neither weak nor strong entropic Leggett-Garg inequalities can be violated

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The Leggett-Garg inequalities probe the classical-quantum boundary by putting limits on the sum of pairwise correlation functions between classical measurement devices that consecutively measured the same quantum system. The apparent violation of these inequalities by standard quantum measurements has cast doubt on quantum mechanics' ability to consistently describe classical objects. Recent work has concluded that these inequalities cannot be violated by either strong or weak projective measurements [1]. Here I consider an entropic version of the Leggett-Garg inequalities that are different from the standard inequalities yet similar in form, and can be defined without reference to any particular observable. I find that the entropic inequalities also cannot be be violated by strong quantum measurements. The entropic inequalities can be extended to describe weak quantum measurements, and I show that these weak entropic Leggett-Garg inequalities cannot be violated either even though the quantum system remains unprojected, because the inequalities describe the classical measurement devices, not the quantum system. I conclude that quantum mechanics adequately describes classical devices, and that we should be careful not to assume that the classical devices accurately describe the quantum system.

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The Born rule — the identification of measurement probability with the squared modulus of quantum amplitudes — has resisted derivation from deeper principles for a century. Every attempt within the Hilbert space framework faces the same structural obstacle: complex amplitudes and real probabilities are different kinds of mathematical objects, and connecting them requires either a new postulate or a covert assumption that smuggles in the probability structure being derived.We argue that in Modular Entropic Gravity (MEG), this obstacle does not arise. The MEG state-to-field map (Axiom 1) sends any quantum mixture ρ = |α|2ρA + |β|2ρB with orthogonal branches to the entropy field configuration Sρ = |α|2SA + |β|2SB . The Born weights |α|2 and |β|2 appear directly as convex coefficients of a real field decomposition — not as complex amplitudes requiring conversion. The factorisation of the measurement map through the coarse-graining channel (established in prior work) guarantees that measurement outcomes respect this convex structure, and we prove a readout faithfulness propositionestablishing that an unbiased branch-resolving apparatus produces outcome frequencies equal to the convex coefficients.The traditional Born rule problem — how do complex amplitudes become real probabilities? — is not answered in MEG. It is rendered unnecessary. In a framework where the physical description is a real entropy field whose branch decomposition carries the Born weights as mixture fractions, the amplitude-to-probability conversion is not a measurement postulate but a feature of the representation change from Hilbert space to entropy field. We directly confront the objection that this merely relocates the Born rule into the density matrix, and show that the relocation changes its logical status: from a postulate connecting two categorically different mathematical objects to an inherited structural property of the physical state representation. The information-geometric results of the MEG programme — the Petz recovery fidelity F 2 = |α|2 and the PLES–Petz equilibrium coincidence — are reinterpreted as independent confirmations of the consistency of this convex structure.

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Granular Entropic Field (GEP): The Quantum Entropic Processor (QEP) as a Thermodynamic Interface for Order

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This document introduces the Quantum Entropic Processor (QEP) as a necessary extension to the Granular Entropic Field (GEP) framework. GEP posits that Entropy is the fundamental force of the universe, and all reality, including spacetime and matter, is defined by the granulation of this field ($\hbar$). The QEP addresses a critical Thermodynamic gap in theories attempting to unify physics and the origin of order: How does the source of Order (The Thermodynamic Initiator of Order, TIO) actively overcome the ubiquitous pressure of Entropic chaos? The QEP is defined as a Negentropic interface—a Processor—that translates the axiomatic requirement for Order (TIO) into physically measurable, low-entropy action within the GEP field. Specifically, the QEP mechanism is hypothesized to perform Active Dynamic Entropic Stressor (DES) Filtering, significantly extending the coherence time of quantum states in biological systems beyond the limits predicted by Standard Quantum Mechanics. This mechanism is presented as an engineering necessity to explain the complex, low-entropy nature of life and consciousness. The paper provides clear, strictly physical and testable predictions for the QEP, including measurable correlations between its efficiency and changes in the local Thermodynamic Gradient of the GEP field.

•Nov 25, 2025•0 citations
The Leggett-Garg inequalities probe the classical-quantum boundary by putting limits on the sum of pairwise correlation functions between classical measurement devices that consecutively measured the same quantum system. The apparent violation of these inequalities by standard quantum measurements has cast doubt on quantum mechanics' ability to consistently describe classical objects. Recent work has concluded that these inequalities cannot be violated by either strong or weak projective measurements [1]. Here I consider an entropic version of the Leggett-Garg inequalities that are different from the standard inequalities yet similar in form, and can be defined without reference to any particular observable. I find that the entropic inequalities also cannot be be violated by strong quantum measurements. The entropic inequalities can be extended to describe weak quantum measurements, and I show that these weak entropic Leggett-Garg inequalities cannot be violated either even though the quantum system remains unprojected, because the inequalities describe the classical measurement devices, not the quantum system. I conclude that quantum mechanics adequately describes classical devices, and that we should be careful not to assume that the classical devices accurately describe the quantum system.
The Born rule — the identification of measurement probability with the squared modulus of quantum amplitudes — has resisted derivation from deeper principles for a century. Every attempt within the Hilbert space framework faces the same structural obstacle: complex amplitudes and real probabilities are different kinds of mathematical objects, and connecting them requires either a new postulate or a covert assumption that smuggles in the probability structure being derived.We argue that in Modular Entropic Gravity (MEG), this obstacle does not arise. The MEG state-to-field map (Axiom 1) sends any quantum mixture ρ = |α|2ρA + |β|2ρB with orthogonal branches to the entropy field configuration Sρ = |α|2SA + |β|2SB . The Born weights |α|2 and |β|2 appear directly as convex coefficients of a real field decomposition — not as complex amplitudes requiring conversion. The factorisation of the measurement map through the coarse-graining channel (established in prior work) guarantees that measurement outcomes respect this convex structure, and we prove a readout faithfulness propositionestablishing that an unbiased branch-resolving apparatus produces outcome frequencies equal to the convex coefficients.The traditional Born rule problem — how do complex amplitudes become real probabilities? — is not answered in MEG. It is rendered unnecessary. In a framework where the physical description is a real entropy field whose branch decomposition carries the Born weights as mixture fractions, the amplitude-to-probability conversion is not a measurement postulate but a feature of the representation change from Hilbert space to entropy field. We directly confront the objection that this merely relocates the Born rule into the density matrix, and show that the relocation changes its logical status: from a postulate connecting two categorically different mathematical objects to an inherited structural property of the physical state representation. The information-geometric results of the MEG programme — the Petz recovery fidelity F 2 = |α|2 and the PLES–Petz equilibrium coincidence — are reinterpreted as independent confirmations of the consistency of this convex structure.
This document introduces the Quantum Entropic Processor (QEP) as a necessary extension to the Granular Entropic Field (GEP) framework. GEP posits that Entropy is the fundamental force of the universe, and all reality, including spacetime and matter, is defined by the granulation of this field (ℏ\hbarℏ). The QEP addresses a critical Thermodynamic gap in theories attempting to unify physics and the origin of order: How does the source of Order (The Thermodynamic Initiator of Order, TIO) actively overcome the ubiquitous pressure of Entropic chaos? The QEP is defined as a Negentropic interface—a Processor—that translates the axiomatic requirement for Order (TIO) into physically measurable, low-entropy action within the GEP field. Specifically, the QEP mechanism is hypothesized to perform Active Dynamic Entropic Stressor (DES) Filtering, significantly extending the coherence time of quantum states in biological systems beyond the limits predicted by Standard Quantum Mechanics. This mechanism is presented as an engineering necessity to explain the complex, low-entropy nature of life and consciousness. The paper provides clear, strictly physical and testable predictions for the QEP, including measurable correlations between its efficiency and changes in the local Thermodynamic Gradient of the GEP field.