Jul 5 – 10, 2021
Europe/Rome timezone

Dark energy and dark matter unification from dynamical space time: observational constraints and cosmological implications

Jul 6, 2021, 9:53 AM
Talk in the parallel session Interacting Dark Matter Interacting Dark Matter


David Benisty (University of Cambridge)


A recently proposed Dynamical Space-time Cosmology (DSC) that unifies dark
energy and dark matter is studied. The general action of this scenario includes a Lagrange
multiplier, which is coupled to the energy momentum tensor and a scalar field which is different
from quintessence. First for various types of potentials we implement a critical point analysis
and we find solutions which lead to cosmic acceleration and under certain conditions to stable
late-time attractors. Then the DSC cosmology is confronted with the latest cosmological
data from low-redshift probes, namely measurements of the Hubble parameter and standard
candles (Pantheon SnIa, Quasi-stellar objects). Performing an overall likelihood analysis and
using the appropriate information criteria we find that the explored DSC models are in very
good agreement with the data. We also find that one of the DSC models shows a small but
non-zero deviation from Λ cosmology, nevertheless the confidence level is close to ∼ 1.5σ

Primary author

David Benisty (University of Cambridge)

Presentation materials