Akarsu, Ö orcid.org/0000-0001-6917-6176, De Felice, A. orcid.org/0000-0002-5556-4693, Di Valentino, E. orcid.org/0000-0001-8408-6961 et al. (5 more authors) (2024) Cosmological constraints on Λs CDM scenario in a type II minimally modified gravity. Physical Review D, 110 (10). 103527. ISSN 2470-0010
Abstract
The idea of a rapid sign-switching cosmological constant (mirror AdS-dS transition) in the late universe at z∼1.7, known as the ΛsCDM model, has significantly improved the fit to observational data and provides a promising scenario for alleviating major cosmological tensions, such as the H0 and S8 tensions. However, in the absence of a fully predictive model, implementing this fit required conjecturing that the dynamics of the linear perturbations are governed by general relativity. Recent work embedding the ΛsCDM model with the Lagrangian of a type II minimally modified gravity known as VCDM has propelled ΛsCDM to a fully predictive model, removing the uncertainty related to the aforementioned assumption; we call this new model ΛsVCDM. In this work, we demonstrate that not only does ΛsCDM fit the data better than the standard ΛCDM model, but the new model, ΛsVCDM, performs even better in alleviating cosmological tensions while also providing a better fit to the data, including cosmic microwave background, baryon acoustic oscillations, type Ia supernovae, and cosmic shear measurements. Our findings highlight the ΛsCDM framework, particularly the ΛsVCDM model, as a compelling alternative to the standard ΛCDM model, especially by successfully alleviating the H0 tension. Additionally, these models predict higher values for σ8, indicating enhanced structuring, albeit with lower present-day matter density parameter values and consequently reduced S8 values, alleviating the S8 tension as well. This demonstrates that the data are well fit by a combination of background and linear perturbations, both having dynamics differing from those of ΛCDM. This paves the way for further exploration of new ways for embedding the sign-switching cosmological constant into other models.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024 The Authors. Except as otherwise noted, this author-accepted version of a journal article published in Physical Review D is made available via the University of Sheffield Research Publications and Copyright Policy under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ |
Keywords: | Particle and High Energy Physics; Physical Sciences |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematical and Physical Sciences |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 13 Dec 2024 12:19 |
Last Modified: | 13 Dec 2024 12:19 |
Status: | Published |
Publisher: | American Physical Society (APS) |
Refereed: | Yes |
Identification Number: | 10.1103/physrevd.110.103527 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:220813 |