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From the Arrow of Time to the Arrow of Life
Earth, Moon, and Planets, 2006Astrobiology, like many (but not all) sciences, must take into account questions of the “Why?”, “Where?”, “How?” and “When?” type. In this introductory chapter, we explain why, in this book, we will only consider two of these questions that are, moreover, deeply interrelated. Chronology is by definition related to the “when?” question but as soon as we
Gargaud, Muriel, Reisse, Jacques
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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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Physical Review D, 1985
The usual proof of the CPT theorem does not apply to theories which include the gravitational field. Nevertheless, it is shown that CPT invariance still holds in these cases provided that, as has recently been proposed, the quantum state of the Universe is defined by a path integral over metrics that are compact without boundary. The observed asymmetry
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The usual proof of the CPT theorem does not apply to theories which include the gravitational field. Nevertheless, it is shown that CPT invariance still holds in these cases provided that, as has recently been proposed, the quantum state of the Universe is defined by a path integral over metrics that are compact without boundary. The observed asymmetry
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New Scientist
The 'arrow of time,' a concept first introduced by Sir Arthur Eddington, reflects the one-way flow of time and its association with various physical asymmetries in thermodynamics, cosmology, quantum mechanics, field theories, and beyond. Yet, the foundations of the arrow of time continues to challenge physicists and philosophers, having profound ...
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The 'arrow of time,' a concept first introduced by Sir Arthur Eddington, reflects the one-way flow of time and its association with various physical asymmetries in thermodynamics, cosmology, quantum mechanics, field theories, and beyond. Yet, the foundations of the arrow of time continues to challenge physicists and philosophers, having profound ...
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1983
Space and time are the most fundamental ideas of the scientist’s picture of the world, and also of the language in which we all describe our thoughts and sensations. We use the concepts of space and time to “relate” ourselves to world phenomena that we and other people observe and to “verify” that what other people report to us as “their observations ...
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Space and time are the most fundamental ideas of the scientist’s picture of the world, and also of the language in which we all describe our thoughts and sensations. We use the concepts of space and time to “relate” ourselves to world phenomena that we and other people observe and to “verify” that what other people report to us as “their observations ...
openaire +1 more source