Journal of Holography Applications in Physics
More About the Spontaneous Breaking of Time Reversal in de Sitter Space
Document Type : Regular article
Author
LITP and Department of Physics, Stanford University, Stanford, CA 94305-4060, USA; Google, Mountain View, CA, USA
Abstract
It is widely thought that the quantum theory of de Sitter space requires the existence of a physical observer in the static patch. What exactly is meant by an observer is unclear; it could be anything from a few photons with energy just above the Gibbons-Hawking temperature to a gravitationally bound cluster of galaxies. In a recent note, I explained that one way the need for observers can arise is from the spontaneous breaking of time-reversal symmetry. This longer paper expands on the subject, filling in conceptual arguments that were implicit but not explicitly stated in the earlier paper.
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Volume 6, Issue 4
May 2026Pages 1-15
- Receive Date: 10 February 2026
- Revise Date: 02 April 2026
- Accept Date: 05 March 2026