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The Physics Teacher, 1967
This article is taken from an introductory textbook by the author, scheduled for publication early in 1968; it represents the concluding section of a chapter on entropy and the second law of thermodynamics. It attempts to draw together the microscopic and macroscopic threads of physics as applied to the concept of time.
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This article is taken from an introductory textbook by the author, scheduled for publication early in 1968; it represents the concluding section of a chapter on entropy and the second law of thermodynamics. It attempts to draw together the microscopic and macroscopic threads of physics as applied to the concept of time.
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Physics Bulletin, 1971
I would like to comment on the recent article by Dr P C W Davies (April 1971 p211), in which the author discusses the direction of time's arrow. The concept of direction implies a reference frame relative to which direction can be determined.
D F A Edwards, P C W Davies, A H Nelson
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I would like to comment on the recent article by Dr P C W Davies (April 1971 p211), in which the author discusses the direction of time's arrow. The concept of direction implies a reference frame relative to which direction can be determined.
D F A Edwards, P C W Davies, A H Nelson
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The Thermodynamical Arrow of Time
1989The thermodynamical arrow of time is characterized by an increase of entropy according to the Second Law, which was postulated by Clausius in 1865 on the basis of Carnot’s process. It can be written in the form (see also (3.1’) on page 57) $$\begin{array}{*{20}{c}} {\frac{{dS}}{{dt}} = {{{\left\{ {\frac{{dS}}{{dt}}} \right\}}}_{{ext}}} + {{{\left\{
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1989
After a stone has been dropped into a pond, one observes concentrically diverging (‘defocussing’) waves. Similarly, after an electric current has been switched on, one finds a retarded electromagnetic field that is moving away from its source. Since the fundamental laws of nature, which describe these phenomena, are invariant under time-reversal, they ...
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After a stone has been dropped into a pond, one observes concentrically diverging (‘defocussing’) waves. Similarly, after an electric current has been switched on, one finds a retarded electromagnetic field that is moving away from its source. Since the fundamental laws of nature, which describe these phenomena, are invariant under time-reversal, they ...
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, 1995 I begin by stating that time is real. To do otherwise (as some famous philosophers from the past have implied) would be ‘philosophical extravagance’[6]. As Shallis [24] put it: ‘The fundamental perception of all mankind is the distinction between day and night, of the phases of the moon and the passage of the planets through the realm of the fixed ...
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2018
Much has been said, conjectured, speculated and dreamed about the origin and evolution of the universe, by scientists and non-scientists alike. Any system of thought claiming to provide an understanding of the physical world, made some statement about the origin and evolution of the universe.
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Much has been said, conjectured, speculated and dreamed about the origin and evolution of the universe, by scientists and non-scientists alike. Any system of thought claiming to provide an understanding of the physical world, made some statement about the origin and evolution of the universe.
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American Journal of Physics, 1962
The time symmetry of the physical laws is discussed. The asymmetry in all statistical processes is found to be related to the tendency for radiation to diverge and that in turn is related to the expansion of the universe. No asymmetry is contained in the laws of electrodynamics, and the choice of the retarded potentials is not a time unsymmetrical step.
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The time symmetry of the physical laws is discussed. The asymmetry in all statistical processes is found to be related to the tendency for radiation to diverge and that in turn is related to the expansion of the universe. No asymmetry is contained in the laws of electrodynamics, and the choice of the retarded potentials is not a time unsymmetrical step.
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2016
We argue that if everything there is in the world is physical, then time has an objective direction. If the fundamental equations of motion are time reversal invariant we show that the direction of time cannot be explained by anything else in physics (e.g. the direction of processes in time) and therefore must be added to physics. We further argue that
Orly Shenker, Meir Hemmo
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We argue that if everything there is in the world is physical, then time has an objective direction. If the fundamental equations of motion are time reversal invariant we show that the direction of time cannot be explained by anything else in physics (e.g. the direction of processes in time) and therefore must be added to physics. We further argue that
Orly Shenker, Meir Hemmo
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Nature, 1956
IT is widely believed that all irreversible mechanical processes involve an increase of entropy, and that ‘classical’ (that is, non-statistical) mechanics, of continuous media as well as of particles, can describe physical processes only in so far as they are reversible in time1. This means that a film taken of a classical process should be reversible,
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IT is widely believed that all irreversible mechanical processes involve an increase of entropy, and that ‘classical’ (that is, non-statistical) mechanics, of continuous media as well as of particles, can describe physical processes only in so far as they are reversible in time1. This means that a film taken of a classical process should be reversible,
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1997
We are commemorating the work of a great scientist — Josef Loschmidt. Inevitably, we look at his achievements through modern eyes. My aim will not only be to look at one of his contributions, the so-called Loschmidt paradox, from my own point of view, inevitably involving more recent knowledge, but also to draw attention to the philosophical background
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We are commemorating the work of a great scientist — Josef Loschmidt. Inevitably, we look at his achievements through modern eyes. My aim will not only be to look at one of his contributions, the so-called Loschmidt paradox, from my own point of view, inevitably involving more recent knowledge, but also to draw attention to the philosophical background
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