# Are Causality Violations Undesirable?

@article{Monroe2008AreCV,
title={Are Causality Violations Undesirable?},
author={Hunter Monroe},
journal={Foundations of Physics},
year={2008},
volume={38},
pages={1065-1069}
}
• Hunter Monroe
• Published 15 September 2006
• Philosophy
• Foundations of Physics
Causality violations are typically seen as unrealistic and undesirable features of a physical model. The following points out three reasons why causality violations, which Bonnor and Steadman identified even in solutions to the Einstein equation referring to ordinary laboratory situations, are not necessarily undesirable. First, a space-time in which every causal curve can be extended into a closed causal curve is singularity free—a necessary property of a globally applicable physical theory…
5 Citations
Putting the Cart Before the Horse: Co-evolution of the Universe and Observers as an Explanatory Hypothesis
• Philosophy
• 2018
This paper considers the fourth option which, at least in principle, is available to us: co-evolution of the universe and observers, and offers two preliminary models along which the co- Evolution hypothesis could be developed further.
The Kerr–Newman–(anti-)de Sitter spacetime: Extremal configurations and electrogeodesics
• Physics
General Relativity and Gravitation
• 2019
We study motion of charged test particles, or electrogeodesics, in the Kerr–Newman–(anti-)de Sitter spacetime. We focus on the equatorial plane and the axis of symmetry where the analysis is
Closed timelike Curves in relativistic Computation
• Computer Science, Mathematics
Parallel Process. Lett.
• 2012
This paper introduces a wormhole based hypercomputation scenario which is free from the common worries, such as the blueshift problem, and discusses the physical reasonability of the scenario.

## References

SHOWING 1-10 OF 22 REFERENCES
COMMENTS, REPLIES AND NOTES: Globally hyperbolic spacetimes can be defined as 'causal' instead of 'strongly causal'
• Philosophy, Mathematics
• 2006
The classical definition of {\em global hyperbolicity} for a spacetime $(M,g)$ comprises two conditions: (A) compactness of the diamonds $J^+(p)\cap J^-(q)$, and (B) strong causality. Here we show
Topology change in classical general relativity
This paper clarifies some aspects of Lorentzian topology change, and it extends to a wider class of spacetimes previous results of Geroch and Tipler that show that topology change is only to be had
The end of the time machine
It is proved that any extendible spacetime U has a maximal extension containing no closed causal curves outside the chronological past of U, and it is interpreted as impossibility (in classical general relativity) of the time machines.
The Large Scale Structure of Space-Time
• Physics
• 1973
The theory of the causal structure of a general space-time is developed, and is used to study black holes and to prove a number of theorems establishing the inevitability of singualarities under certain conditions.
No time machines in classical general relativity
Irrespective of local conditions imposed on the metric, any extendible spacetime U has a maximal extension containing no closed causal curves outside the chronological past of U. We prove this fact
Topological censorship.
• Physics
Physical review letters
• 1993
It is shown that the topology of physically reasonable isolated systems is shrouded from distant observers, or in other words there is a topological censorship principle.
CLOSED TIMELIKE CURVES IN CLASSICAL RELATIVITY
Spacetimes of general relativity containing closed timelike curves (CTC) are usually dismissed as non-physical. However, it is now known that CTC may appear in spacetimes modelling simple laboratory
Exact solutions of the Einstein-Maxwell equations with closed timelike curves
• Physics
• 2005
We examine two electrovac spacetimes, the Kerr-Newman solution and another due to Perjes, which represent single charged, rotating, magnetic objects. Both contain regions with closed timelike curves