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Cosmos and history

The Arrow of Time

Ted Dace

Published Dec 12, 2018• 1 citation
OpenAlex

Abstract

The foundation of irreversible, probabilistic time -- the classical time of conscious observation -- is the reversible and deterministic quantum time of the wave function. The tendency in physics is to regard time in the abstract, a mere parameter devoid of inherent direction, implying that a concept of real time must begin with irreversibility. In reality time has no need for irreversibility, and every invocation of time implies becoming or flow. Neither symmetry under time reversal, of which Newton was well aware, nor the absence of an absolute parameter, as in relativity, negates temporal passage. Far from encapsulating time, irreversibility is a secondary property dependent on the emergence of distinct moments from the ceaseless presence charted by the wave function.

Related papers

Time flow and reversibility in a probabilistic universe : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Philosophy at Massey University

Andrew Holster

A fundamental problem in understanding the nature of time is to explain its 'directionality'. The commonplace view is that this directionality is provided by the 'flow of time'. Unfortunately this concept of 'time flow', which seems to make perfect sense to us in our everyday lives, has resisted philosophical and scientific analysis so well that today it is widely regarded as having no place in the scientific account of the world. Instead, various alternative physical concepts of the directionality of time have been developed, principally the notions of the time reversibility of physical laws or theories, and of the time asymmetry of physical processes. It is frequently argued by philosophers of physics that the scientific account of the directionality of time must be framed entirely in terms of these physical notions. The thesis of the present work is that this conclusion has been reached far too hastily. It is argued that the concept of time flow is a legitimate physical concept, and furthermore, that time flow plays a real part in quantum theory. A number of conceptual investigations are necessary to support this argument. Firstly, it is necessary to give an analysis of what a physical theory of time flow might be like, and how it might be empirically established. This is given in Chapter One, which at the same time is an overview of the results of later chapters. It is found in Chapter One that the concept of physical time flow has an important connection with the concept of time reversibility, which makes it necessary to give an analysis of this notion. A detailed discussion of reversibility and time symmetry is given in Chapters Two to Five. Here it is demonstrated that the orthodox analysis of the reversibility of probabilistic theories is flawed. This conclusion allows it to be shown, in Chapter Six, that, contrary to current scientific belief, quantum theory is profoundly irreversible. This result, together with the argument of Chapter One, allows a strong prima facie case for an interpretation of quantum probabilities as involving time flow to be given. However, because of the traditional problems with the notion of time flow, for this interpretation to become respectable it needs to be demonstrated that it is possible to construct a formal model of a physical ontology in which time flow can be represented. This is undertaken in Chapter Seven. In Chapter Eight, various points about the role of probabilities in quantum theory are discussed. Finally, in Chapter Nine, the implications of relativity theory for the proposed theory of time flow are considered. It is found that relativity theory poses a serious problem for a physical theory of time flow, but the implications of relativity theory for the proposed interpretation of quantum probabilities is not clear because of deeper foundational problems with quantum theory.

•Jan 1, 1990•0 citations

The Irreversibility of Time and the Origin of the Wave Function

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The fundamental laws of physics (Newton, Maxwell, Schrödinger) are time-reversible, yet our macroscopic experience is governed by an irreversible arrow of time. This paradox, along with the probabilistic nature of the quantum wave function, remains a central puzzle in foundational physics. In this work, we propose a unified resolution based on Unified Field Dynamics (UFD). We postulate that the configuration space Q is not a static arena but a dynamic manifold subject to continuous stochastic agitation (Sigma dW). We derive the Second Law of Thermodynamics not as a statistical artifact, but as a geometric necessity: the dissipative drift -grad J drives the system towards states of lower potential complexity, defining a unique temporal direction. Furthermore, we demonstrate that in the regime of equilibrium between this dissipation and the vacuum noise, the dynamics of the field q are governed by a complex diffusion equation that is mathematically isomorphic to the Schrödinger Equation. We explicitly address the Wallstrom objection regarding phase quantization by invoking the topological nature of UFD solitons derived in previous work. We conclude that "Quantum Mechanics" is the hydrodynamics of the stochastic vacuum, and "Time" is the relaxation of the universe towards its geometric ground state.

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The Time Asymmetry of Quantum Mechanics and Concepts of Physical Directionality of Time. Part 1. T Asymmetry of Quantum Probability Laws.

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This is Part 1 of a four part paper, intended to redress some of the most fundamental confusions in the subject of physical time directionality, and represent the concepts accurately. There are widespread fallacies in the subject that need to be corrected in introductory courses for physics students and philosophers. Parts 1 and 2 are about quantum mechanics, Part 3 is about fundamental concepts, and Part 4 is about cosmology. We start in Part 1 by analysing the time reversal symmetry of quantum probability laws. Time reversal symmetry is defined as the property of invariance under the time reversal transformation, T: t -> -t. It is shown that quantum mechanics (classical or relativistic) is strongly time asymmetric in its probability laws. This contradicts the orthodox analysis, found throughout the conventional literature on physical time, which claims that quantum mechanics is time symmetric or reversible. This is widely claimed as settled scientific fact, and large philosophical and scientific conclusions are drawn from it. But it is an error. The fact is that while quantum mechanics is widely claimed to be reversible on the basis of two formal mathematical properties (that it does have), these properties do not represent invariance under the time reversal transformation. A recent experiment (Batalhao at alia, 2015) showing irreversibility of quantum thermodynamics is discussed as an illustration of this result. Most physicists remain unaware of the errors, decades after they were first demonstrated. Orthodox specialists in the philosophy of time who are aware of the error continue to refer to the ‘time symmetry’ or ‘reversibility’ of quantum mechanics anyway – and exploit the ambiguity to claim false implications about physical time reversal symmetry in nature. The excuse for perpetrating the confusion is that, since it is has now become customary to refer to the formal properties of quantum mechanics as ‘reversibility’ or ‘time reversal symmetry’, we should just keep referring to them by this name, even though they are not time reversal symmetry. This causes endless confusion, in attempts to explain the physical irreversibility of our universe, and in philosophical discussions of implications of physics for the nature of time. The failure of time reversal symmetry in quantum mechanics changes the interpretation of modern physics in a deep way. It changes the problem of explaining the real irreversibility found throughout nature.

•Dec 1, 2017•0 citations

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Atoms•Oct 26, 2025•1 citation

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Abstract For decades, researchers have sought to understand how the irreversibility of the surrounding world emerges from the seemingly time-symmetric, fundamental laws of physics. Quantum mechanics conjectured a clue that final irreversibility is set by the measurement procedure and that the time-reversal requires complex conjugation of the wave function, which is overly complex to spontaneously appear in nature. Building on this Landau-Wigner conjecture, it became possible to demonstrate that time-reversal is exponentially improbable in a virgin nature and to design an algorithm artificially reversing a time arrow for a given quantum state on the IBM quantum computer. However, the implemented arrow-of-time reversal embraced only the known states initially disentangled from the thermodynamic reservoir. Here we develop a procedure for reversing the temporal evolution of an arbitrary unknown quantum state. This opens the route for general universal algorithms sending temporal evolution of an arbitrary system backward in time.

arXiv:1912.12036•Communications Physics•Jul 21, 2020•3 citations

Causality and Reversibility in Irreversible Time

Sergey M. Korotaev

In the book the idea of irreversibility as an inherent property of time is developed theoretically and experimentally. The matter is related with causality, and the method of causal analysis is presented. The quantum causal analysis helps understand the principle of week causality which admits extraction of information from the future without the classical paradoxes. It implies a possibility of observation of the future as the existing reality. So, the acceptance of time irreversibility leads to a striking manifestation of reversibility – signaling in reverse time. Quantum insight allows considering correlations of the distant irreversible processes as nonlocal ones originated from a macroscopic entanglement. The experimental approach to study of macroscopic nonlocality is discussed, and design of the experimental setup is described. The results of experiments on macroscopic nonlocal correlations, the signals in reverse time and their application to the forecast of large-scale random processes are expounded.

•Jan 1, 2011•10 citations
The foundation of irreversible, probabilistic time -- the classical time of conscious observation -- is the reversible and deterministic quantum time of the wave function. The tendency in physics is to regard time in the abstract, a mere parameter devoid of inherent direction, implying that a concept of real time must begin with irreversibility. In reality time has no need for irreversibility, and every invocation of time implies becoming or flow. Neither symmetry under time reversal, of which Newton was well aware, nor the absence of an absolute parameter, as in relativity, negates temporal passage. Far from encapsulating time, irreversibility is a secondary property dependent on the emergence of distinct moments from the ceaseless presence charted by the wave function.
A fundamental problem in understanding the nature of time is to explain its 'directionality'. The commonplace view is that this directionality is provided by the 'flow of time'. Unfortunately this concept of 'time flow', which seems to make perfect sense to us in our everyday lives, has resisted philosophical and scientific analysis so well that today it is widely regarded as having no place in the scientific account of the world. Instead, various alternative physical concepts of the directionality of time have been developed, principally the notions of the time reversibility of physical laws or theories, and of the time asymmetry of physical processes. It is frequently argued by philosophers of physics that the scientific account of the directionality of time must be framed entirely in terms of these physical notions. The thesis of the present work is that this conclusion has been reached far too hastily. It is argued that the concept of time flow is a legitimate physical concept, and furthermore, that time flow plays a real part in quantum theory. A number of conceptual investigations are necessary to support this argument. Firstly, it is necessary to give an analysis of what a physical theory of time flow might be like, and how it might be empirically established. This is given in Chapter One, which at the same time is an overview of the results of later chapters. It is found in Chapter One that the concept of physical time flow has an important connection with the concept of time reversibility, which makes it necessary to give an analysis of this notion. A detailed discussion of reversibility and time symmetry is given in Chapters Two to Five. Here it is demonstrated that the orthodox analysis of the reversibility of probabilistic theories is flawed. This conclusion allows it to be shown, in Chapter Six, that, contrary to current scientific belief, quantum theory is profoundly irreversible. This result, together with the argument of Chapter One, allows a strong prima facie case for an interpretation of quantum probabilities as involving time flow to be given. However, because of the traditional problems with the notion of time flow, for this interpretation to become respectable it needs to be demonstrated that it is possible to construct a formal model of a physical ontology in which time flow can be represented. This is undertaken in Chapter Seven. In Chapter Eight, various points about the role of probabilities in quantum theory are discussed. Finally, in Chapter Nine, the implications of relativity theory for the proposed theory of time flow are considered. It is found that relativity theory poses a serious problem for a physical theory of time flow, but the implications of relativity theory for the proposed interpretation of quantum probabilities is not clear because of deeper foundational problems with quantum theory.
The fundamental laws of physics (Newton, Maxwell, Schrödinger) are time-reversible, yet our macroscopic experience is governed by an irreversible arrow of time. This paradox, along with the probabilistic nature of the quantum wave function, remains a central puzzle in foundational physics. In this work, we propose a unified resolution based on Unified Field Dynamics (UFD). We postulate that the configuration space Q is not a static arena but a dynamic manifold subject to continuous stochastic agitation (Sigma dW). We derive the Second Law of Thermodynamics not as a statistical artifact, but as a geometric necessity: the dissipative drift -grad J drives the system towards states of lower potential complexity, defining a unique temporal direction. Furthermore, we demonstrate that in the regime of equilibrium between this dissipation and the vacuum noise, the dynamics of the field q are governed by a complex diffusion equation that is mathematically isomorphic to the Schrödinger Equation. We explicitly address the Wallstrom objection regarding phase quantization by invoking the topological nature of UFD solitons derived in previous work. We conclude that "Quantum Mechanics" is the hydrodynamics of the stochastic vacuum, and "Time" is the relaxation of the universe towards its geometric ground state.
This is Part 1 of a four part paper, intended to redress some of the most fundamental confusions in the subject of physical time directionality, and represent the concepts accurately. There are widespread fallacies in the subject that need to be corrected in introductory courses for physics students and philosophers. Parts 1 and 2 are about quantum mechanics, Part 3 is about fundamental concepts, and Part 4 is about cosmology. We start in Part 1 by analysing the time reversal symmetry of quantum probability laws. Time reversal symmetry is defined as the property of invariance under the time reversal transformation, T: t -> -t. It is shown that quantum mechanics (classical or relativistic) is strongly time asymmetric in its probability laws. This contradicts the orthodox analysis, found throughout the conventional literature on physical time, which claims that quantum mechanics is time symmetric or reversible. This is widely claimed as settled scientific fact, and large philosophical and scientific conclusions are drawn from it. But it is an error. The fact is that while quantum mechanics is widely claimed to be reversible on the basis of two formal mathematical properties (that it does have), these properties do not represent invariance under the time reversal transformation. A recent experiment (Batalhao at alia, 2015) showing irreversibility of quantum thermodynamics is discussed as an illustration of this result. Most physicists remain unaware of the errors, decades after they were first demonstrated. Orthodox specialists in the philosophy of time who are aware of the error continue to refer to the ‘time symmetry’ or ‘reversibility’ of quantum mechanics anyway – and exploit the ambiguity to claim false implications about physical time reversal symmetry in nature. The excuse for perpetrating the confusion is that, since it is has now become customary to refer to the formal properties of quantum mechanics as ‘reversibility’ or ‘time reversal symmetry’, we should just keep referring to them by this name, even though they are not time reversal symmetry. This causes endless confusion, in attempts to explain the physical irreversibility of our universe, and in philosophical discussions of implications of physics for the nature of time. The failure of time reversal symmetry in quantum mechanics changes the interpretation of modern physics in a deep way. It changes the problem of explaining the real irreversibility found throughout nature.
Abstract For decades, researchers have sought to understand how the irreversibility of the surrounding world emerges from the seemingly time-symmetric, fundamental laws of physics. Quantum mechanics conjectured a clue that final irreversibility is set by the measurement procedure and that the time-reversal requires complex conjugation of the wave function, which is overly complex to spontaneously appear in nature. Building on this Landau-Wigner conjecture, it became possible to demonstrate that time-reversal is exponentially improbable in a virgin nature and to design an algorithm artificially reversing a time arrow for a given quantum state on the IBM quantum computer. However, the implemented arrow-of-time reversal embraced only the known states initially disentangled from the thermodynamic reservoir. Here we develop a procedure for reversing the temporal evolution of an arbitrary unknown quantum state. This opens the route for general universal algorithms sending temporal evolution of an arbitrary system backward in time.
In the book the idea of irreversibility as an inherent property of time is developed theoretically and experimentally. The matter is related with causality, and the method of causal analysis is presented. The quantum causal analysis helps understand the principle of week causality which admits extraction of information from the future without the classical paradoxes. It implies a possibility of observation of the future as the existing reality. So, the acceptance of time irreversibility leads to a striking manifestation of reversibility – signaling in reverse time. Quantum insight allows considering correlations of the distant irreversible processes as nonlocal ones originated from a macroscopic entanglement. The experimental approach to study of macroscopic nonlocality is discussed, and design of the experimental setup is described. The results of experiments on macroscopic nonlocal correlations, the signals in reverse time and their application to the forecast of large-scale random processes are expounded.