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Off-shell dark matter: a cosmological relic of quantum gravity

Saravani, Mehdi; Afshordi, Niayesh


Mehdi Saravani

Niayesh Afshordi


We study a novel proposal for the origin of cosmological cold dark matter (CDM) which is rooted in the quantum nature of spacetime. In this model, off-shell modes of quantum fields can exist in asymptotic states as a result of spacetime nonlocality (expected in generic theories of quantum gravity), and play the role of CDM, which we dub off-shell dark matter (OfDM). However, their rate of production is suppressed by the scale of non-locality (e.g. Planck length). As a result, we show that OfDM is only produced in the first moments of big bang, and then effectively decouples (except through its gravitational interactions). We examine the observational predictions of this model: In the context of cosmic inflation, we show that this proposal relates the reheating temperature to the inflaton mass, which narrows down the uncertainty in the number of e-foldings of specific inflationary scenarios. We also demonstrate that OfDM is indeed cold, and discuss potentially observable signatures on small scale matter power spectrum.


Saravani, M., & Afshordi, N. (2017). Off-shell dark matter: a cosmological relic of quantum gravity. Physical Review D, 95(4), Article 043514.

Journal Article Type Article
Acceptance Date Jan 25, 2017
Online Publication Date Feb 17, 2017
Publication Date Feb 15, 2017
Deposit Date Jul 4, 2017
Publicly Available Date Jul 4, 2017
Journal Physical Review D
Print ISSN 2470-0010
Electronic ISSN 2470-0029
Publisher American Physical Society
Peer Reviewed Peer Reviewed
Volume 95
Issue 4
Article Number 043514
Keywords Dark matter, Quantum gravity
Public URL
Publisher URL
Additional Information ©2017 American Physical Society


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