Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2604.16564 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866918453036711936 |
|---|---|
| author | Kumar, D. Revanth Yadav, Santosh Kumar Kadam, S. A. |
| author_facet | Kumar, D. Revanth Yadav, Santosh Kumar Kadam, S. A. |
| contents | In this article, we investigate two phenomenological decaying vacuum cosmological models describing the accelerated expansion of the Universe. We constrain the model parameters using a Markov Chain Monte Carlo (MCMC) technique with recent datasets, including cosmic chronometer (CC), Pantheon+SH0ES (PPS), and DESI BAO data release (DR2). Our analysis provides constraints from PPS, PPS+CC, and the joint PPS+CC+DR2 datasets for both models. All datasets favor $H_0 \simeq 72.53$--$73.01~\mathrm{Km\,s^{-1}\,Mpc^{-1}}$, while $Ω_{m0}$ is higher with PPS alone and decreases to standard paradigm estimates with the inclusion of additional data. The evolution parameter is $n \approx 0.30$ from joint analysis, indicating a mild deviation from the $Λ$CDM framework. Furthermore, the physical behavior of the models is examined through the deceleration parameter and the total equation of state, confirming a smooth transition from past deceleration expansion to the present accelerated expansion. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2604_16564 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | Observational tests of \texorpdfstring{$Λ(t)$}{Lambda(t)} cosmology in light of DESI DR2 Kumar, D. Revanth Yadav, Santosh Kumar Kadam, S. A. General Physics In this article, we investigate two phenomenological decaying vacuum cosmological models describing the accelerated expansion of the Universe. We constrain the model parameters using a Markov Chain Monte Carlo (MCMC) technique with recent datasets, including cosmic chronometer (CC), Pantheon+SH0ES (PPS), and DESI BAO data release (DR2). Our analysis provides constraints from PPS, PPS+CC, and the joint PPS+CC+DR2 datasets for both models. All datasets favor $H_0 \simeq 72.53$--$73.01~\mathrm{Km\,s^{-1}\,Mpc^{-1}}$, while $Ω_{m0}$ is higher with PPS alone and decreases to standard paradigm estimates with the inclusion of additional data. The evolution parameter is $n \approx 0.30$ from joint analysis, indicating a mild deviation from the $Λ$CDM framework. Furthermore, the physical behavior of the models is examined through the deceleration parameter and the total equation of state, confirming a smooth transition from past deceleration expansion to the present accelerated expansion. |
| title | Observational tests of \texorpdfstring{$Λ(t)$}{Lambda(t)} cosmology in light of DESI DR2 |
| topic | General Physics |
| url | https://arxiv.org/abs/2604.16564 |