Theory of interacting vector dark energy and fluid
Issued Date
2024-10-01
Resource Type
eISSN
14757516
Scopus ID
2-s2.0-85208385657
Journal Title
Journal of Cosmology and Astroparticle Physics
Volume
2024
Issue
10
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of Cosmology and Astroparticle Physics Vol.2024 No.10 (2024)
Suggested Citation
Pookkillath M.C., Koyama K. Theory of interacting vector dark energy and fluid. Journal of Cosmology and Astroparticle Physics Vol.2024 No.10 (2024). doi:10.1088/1475-7516/2024/10/105 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/102028
Title
Theory of interacting vector dark energy and fluid
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Author's Affiliation
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Abstract
In this work, we study interaction between dark energy and dark matter, where dark energy is described by a massive vector field, and dark matter is modelled as a fluid. We present a new interaction term, which affects only perturbations and can give interesting phenomenology. Then we present a general Lagrangian for the interacting vector dark energy with dark matter. For the dark energy, we choose Proca theory with G 3 term to study its phenomenological consequence. For this model, we explore both background and perturbation dynamics. We also present the no-ghost condition for tensor modes, vector modes and scalar modes. Subsequently, we also study the evolution of the overdensities of both baryon and cold dark matter in the high-k limit. We show that the effective gravitational coupling is modified for cold dark matter and baryon. We also choose a simple concrete model and numerically show a suppression of the effective gravitational coupling for cold dark matter. However, in this simple model, the suppression of the effective gravitational coupling does not result in a suppression of the matter overdensity compared to that in the ΛCDM model due to the modified background expansion.