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Title: 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 topology-changing processes in general. Even though topology-changing 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:
 [1]
  1. (Theoretical Division, T-8, Mail Stop B-285, 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; SPACE-TIME; 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 topology-changing processes in general. Even though topology-changing 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
}
  • Under certain circumstances, the collision of magnetic monopoles, topologically locked-in regions of false vacuum, leads to topological inflation and the creation of baby universes. The future evolution of initial data represented by the two incoming monopoles may contain a timelike singularity but this need not be the case. We discuss the global structure of the spacetime associated with monopole collisions and also that of topological inflation. We suggest that topological inflation within magnetic monopoles leads to an eternally reproducing universe. {copyright} {ital 1999} {ital The American Physical Society}
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