Book contents
- Frontmatter
- Contents
- Contributors
- Symposium Program
- Papers from both Volumes Classified by Subject
- Preface
- Charles W. Misner: Insight and Discovery
- Remarks Concerning the Geometries of Gravity and Gauge Fields
- Gravity and Unification of Fundamental Interactions
- Minisuperspaces: Symmetries and Quantization
- Quantum Cosmology
- A Pictorial History of some Gravitational Instantons
- No Time Machines from Lightlike Sources in 2+1 Gravity
- Inhomogeneity and Anisotropy Generation in FRW Cosmologies
- Misner, Kinks and Black Holes
- The Quantum Mechanics of Closed Systems
- Cosmological Vacuum Phase Transitions
- Minisuperspace as a Quantum Open System
- Ricci Flow on Minisuperspaces and the Geometry-Topology Problem
- Classical and Quantum Dynamics of Black Hole Interiors
- Matter Time in Canonical Quantum Gravity
- The Isotropy and Homogeneity of the Universe
- Recent Advances in ADM Reduction
- Some Progress in Classical Canonical Gravity
- Harmonic Map Formulation of Colliding Electrovac Plane Waves
- Geometry, the Renormalization Group and Gravity
- An Example of Indeterminacy in the Time-Development of “Already Unified Field Theory”: A Collision between Electomagnetic Plane Waves
- Non-static Metrics of Hiscock-Gott Type
- Non-Standard Phase Space Variables, Quantization and Path-Integrals, or Little Ado about Much
- The Present Status of the Decaying Neutrino Theory
- Exploiting the Computer to Investigate Black Holes and Cosmic Censorship
- Misner Space as a Prototype for Almost Any Pathology
- Relativity and Rotation
- The First Law of Black Hole Mechanics
- Gravitational Radiation Antenna Observations
- The Back-Reaction is Never Negligible: Entropy of Black Holes and Radiation
- Toward a Thesis Topic
- Charles Misner: A Celebration of Memories
- Curriculum Vitae of C. W. Misner
- Ph. D. Theses supervised by C. W. Misner
- List of Publications of C. W. Misner
The Quantum Mechanics of Closed Systems
Published online by Cambridge University Press: 03 February 2010
- Frontmatter
- Contents
- Contributors
- Symposium Program
- Papers from both Volumes Classified by Subject
- Preface
- Charles W. Misner: Insight and Discovery
- Remarks Concerning the Geometries of Gravity and Gauge Fields
- Gravity and Unification of Fundamental Interactions
- Minisuperspaces: Symmetries and Quantization
- Quantum Cosmology
- A Pictorial History of some Gravitational Instantons
- No Time Machines from Lightlike Sources in 2+1 Gravity
- Inhomogeneity and Anisotropy Generation in FRW Cosmologies
- Misner, Kinks and Black Holes
- The Quantum Mechanics of Closed Systems
- Cosmological Vacuum Phase Transitions
- Minisuperspace as a Quantum Open System
- Ricci Flow on Minisuperspaces and the Geometry-Topology Problem
- Classical and Quantum Dynamics of Black Hole Interiors
- Matter Time in Canonical Quantum Gravity
- The Isotropy and Homogeneity of the Universe
- Recent Advances in ADM Reduction
- Some Progress in Classical Canonical Gravity
- Harmonic Map Formulation of Colliding Electrovac Plane Waves
- Geometry, the Renormalization Group and Gravity
- An Example of Indeterminacy in the Time-Development of “Already Unified Field Theory”: A Collision between Electomagnetic Plane Waves
- Non-static Metrics of Hiscock-Gott Type
- Non-Standard Phase Space Variables, Quantization and Path-Integrals, or Little Ado about Much
- The Present Status of the Decaying Neutrino Theory
- Exploiting the Computer to Investigate Black Holes and Cosmic Censorship
- Misner Space as a Prototype for Almost Any Pathology
- Relativity and Rotation
- The First Law of Black Hole Mechanics
- Gravitational Radiation Antenna Observations
- The Back-Reaction is Never Negligible: Entropy of Black Holes and Radiation
- Toward a Thesis Topic
- Charles Misner: A Celebration of Memories
- Curriculum Vitae of C. W. Misner
- Ph. D. Theses supervised by C. W. Misner
- List of Publications of C. W. Misner
Summary
ABSTRACT
A pedagogical introduction is given to the quantum mechanics of closed systems, most generally the universe as a whole. Quantum mechanics aims at predicting the probabilities of alternative coarse-grained time histories of a closed system. Not every set of alternative coarse-grained histories that can be described may be consistently assigned probabilities because of quantum mechanical interference between individual histories of the set. In “Copenhagen” quantum mechanics, probabilities can be assigned to histories of a subsystem that have been “measured”. In the quantum mechanics of closed systems, containing both observer and observed, probabilities are assigned to those sets of alternative histories for which there is negligible interference between individual histories as a consequence of the system's initial condition and dynamics. Such sets of histories are said to decohere. We define decoherence for closed systems in the simplified case when quantum gravity can be neglected and the initial state is pure. Typical mechanisms of decoherence that are widespread in our universe are illustrated.
Copenhagen quantum mechanics is an approximation to the more general quantum framework of closed subsystems. It is appropriate when there is an approximately isolated subsystem that is a participant in a measurement situation in which (among other things) the decoherence of alternative registrations of the apparatus can be idealized as exact.
Since the quantum mechanics of closed systems does not posit the existence of the quasiclassical domain of everyday experience, the domain of the approximate aplicability of classical physics must be explained.
- Type
- Chapter
- Information
- Directions in General RelativityProceedings of the 1993 International Symposium, Maryland: Papers in Honor of Charles Misner, pp. 104 - 124Publisher: Cambridge University PressPrint publication year: 1993
- 9
- Cited by