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arXiv · gr-qc/0703131

Uniqueness of de Sitter space

Gregory J. Galloway·Didier A. Solis
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Abstract

All inextendible null geodesics in four dimensional de Sitter space dS^4 are complete and globally achronal. This achronality is related to the fact that all observer horizons in dS^4 are eternal, i.e. extend from future infinity scri^+ all the way back to past infinity scri^-. We show that the property of having a null line (inextendible achronal null geodesic) that extends from scri^- to scri^+ characterizes dS^4 among all globally hyperbolic and asymptotically de Sitter spacetimes satisfying the vacuum Einstein equations with positive cosmological constant. This result is then further extended to allow for a class of matter models that includes perfect fluids.

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Gregory J. Galloway, Didier A. Solis. 2007-03-27. Uniqueness of de Sitter space. https://doi.org/10.1088/0264-9381%2F24%2F11%2F021

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