Wormholes, baby universes, and causality

Journal Article · Thu Feb 15 00:00:00 EST 1990 · Physical Review, D (Particles Fields); (USA)

DOI:https://doi.org/10.1103/PhysRevD.41.1116· OSTI ID:6904477

Visser, M ^[1]

---

1. Theoretical Division, T-8, Mail Stop B-285, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (US)

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.

• OSTI ID: 6904477
• Journal Information: Physical Review, D (Particles Fields); (USA), Vol. 41:4; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

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