Wormholes, baby universes, and causality
Abstract
In this paper wormholes defined on a Minkowski signature manifold are considered, both at the classical and quantum levels. It is argued that causality in quantum gravity may best be imposed by restricting the functional integral to include only causal Lorentzian spacetimes. Subject to this assumption, one can put very tight constraints on the quantum behavior of wormholes, their cousins the baby universes, and topologychanging processes in general. Even though topologychanging processes are tightly constrained, this still allows very interesting geometrical (rather than topological) effects. In particular, the laboratory construction of baby universes is {ital not} prohibited provided that the umbilical cord'' is never cut. Methods for relaxing these causality constraints are also discussed.
 Authors:
 (Theoretical Division, T8, Mail Stop B285, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (US))
 Publication Date:
 OSTI Identifier:
 6904477
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review, D (Particles Fields); (USA); Journal Volume: 41:4
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; UNIVERSE; CAUSALITY; BOUNDARY CONDITIONS; CLASSICAL MECHANICS; EUCLIDEAN SPACE; METRICS; MINKOWSKI SPACE; QUANTUM GRAVITY; QUANTUM MECHANICS; SPACETIME; TOPOLOGY; FIELD THEORIES; MATHEMATICAL SPACE; MATHEMATICS; MECHANICS; QUANTUM FIELD THEORY; RIEMANN SPACE; SPACE 640106*  Astrophysics & Cosmology Cosmology
Citation Formats
Visser, M. Wormholes, baby universes, and causality. United States: N. p., 1990.
Web. doi:10.1103/PhysRevD.41.1116.
Visser, M. Wormholes, baby universes, and causality. United States. doi:10.1103/PhysRevD.41.1116.
Visser, M. 1990.
"Wormholes, baby universes, and causality". United States.
doi:10.1103/PhysRevD.41.1116.
@article{osti_6904477,
title = {Wormholes, baby universes, and causality},
author = {Visser, M.},
abstractNote = {In this paper wormholes defined on a Minkowski signature manifold are considered, both at the classical and quantum levels. It is argued that causality in quantum gravity may best be imposed by restricting the functional integral to include only causal Lorentzian spacetimes. Subject to this assumption, one can put very tight constraints on the quantum behavior of wormholes, their cousins the baby universes, and topologychanging processes in general. Even though topologychanging processes are tightly constrained, this still allows very interesting geometrical (rather than topological) effects. In particular, the laboratory construction of baby universes is {ital not} prohibited provided that the umbilical cord'' is never cut. Methods for relaxing these causality constraints are also discussed.},
doi = {10.1103/PhysRevD.41.1116},
journal = {Physical Review, D (Particles Fields); (USA)},
number = ,
volume = 41:4,
place = {United States},
year = 1990,
month = 2
}

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