Everything You Always Wanted to Know About How Causal Set Theory Can Help with Open Questions in Cosmology, but Were Afraid to Ask

Abstract

We briefly survey open questions in cosmology that either have been or could potentially be addressed with the help of the causal set theory approach to quantum gravity. Our discussion includes topics ranging from dark matter and dark energy to primordial quantum fluctuations and horizon entropy. By putting together all in one place these cosmologically relevant directions of work within causal set theory, we hope to impart a bird's-eye view of this important research theme.

arXiv comment21 pages, 6 figures. Invited brief review for MPLA (World Scientific)

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• Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the string-theoretical Swampland Programme
• In-in correlators and scattering amplitudes on a causal set