General Relativity and Quantum Cosmology, abstract
gr-qc/0607134

From: Hunter Monroe [view email]

Date: Mon, 31 Jul 2006 04:30:09 GMT (21kb)

Censorship of Chronological Violations

Authors: Hunter Monroe

Comments: RevTeX 4, 20 pages, no figures

Subj-class: General Relativity and Quantum Cosmology; Differential Geometry

Rich non-arbitrary topological change may occur in a relativistic vacuum space-time that violates chronology at every point. However, each closed timelike curve (CTC) is typically "censored" by passing through a wormhole's event horizon, and a Cauchy-like surface may exist through which all timelike curves pass once and only once before crossing an event horizon. All CTCs in a time-orientable space-time must pass through a wormhole; otherwise the CTC could be deformed as a CTC to a non-time-orientable point. Therefore, if all wormholes have event horizons, there is chronology protection against uncensored CTCs, and the universe is safe for those historians who cannot see through event horizons. An indicator of a space-time's completeness which is conformally invariant, unlike geodesic or b-completeness, is that no causal boundary exists, which implies that the entire space-time is a chronology violating set. Such "causally complete" space-times fail to satisfy assumptions of the topological censorship theorem and a wide range of singularity theorems; causal completeness implies geodesic and b-completeness.

If a wormhole's two mouths are nearby, its event horizon as a one-way membrane causes the wormhole to propagate, mimicking the behavior of a photon. If the two mouths are not nearby, they mimic the behavior of a fermion and its anti-particle. Energy-momentum conservation implies that these pseudo-photons can be created or destroyed only in multiples of 2 (similar to results of Gibbons and Hawking), and that their destruction creates gravitational waves. The time-reversed phenomenon would be a collision of (non-planar) gravitational waves that creates entangled pseudo-photon pair.

http://arxiv.org/abs/gr-qc/0607134