Gespeichert in:
| Hauptverfasser: | , |
|---|---|
| Format: | Preprint |
| Veröffentlicht: |
2026
|
| Schlagworte: | |
| Online-Zugang: | https://arxiv.org/abs/2601.18825 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| _version_ | 1866918307532111872 |
|---|---|
| author | Shahidi, Shahab Farahzad, Sedigheh |
| author_facet | Shahidi, Shahab Farahzad, Sedigheh |
| contents | A new realization of the matter Lagrangian is introduced which models the dark energy component as a non-standard combination of thermodynamics quantities of the baryonic matter. We will prove that the present realization is independent of existing models with matter-geometry couplings and has a property that the energy-momentum tensor of both baryonic matter and dark energy is conserved separately. We further show that two possible choices of the matter Lagrangian in the $Λ$CDM model are not totally equivalent and investigate the background and perturbative constraints on the form of matter Lagrangian. We will also investigate cosmological implications of a test model with logarithmic DE and obtain the model parameters by confronting the model with observational data on the cosmic chronometers, Pantheon$^+$ and $fσ_8$ datasets. We will also explain in details the predictions of the model on the late time behavior of the universe and compare the result with $Λ$CDM model. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2601_18825 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | Dark energy and a new realization of the matter Lagrangian Shahidi, Shahab Farahzad, Sedigheh General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics A new realization of the matter Lagrangian is introduced which models the dark energy component as a non-standard combination of thermodynamics quantities of the baryonic matter. We will prove that the present realization is independent of existing models with matter-geometry couplings and has a property that the energy-momentum tensor of both baryonic matter and dark energy is conserved separately. We further show that two possible choices of the matter Lagrangian in the $Λ$CDM model are not totally equivalent and investigate the background and perturbative constraints on the form of matter Lagrangian. We will also investigate cosmological implications of a test model with logarithmic DE and obtain the model parameters by confronting the model with observational data on the cosmic chronometers, Pantheon$^+$ and $fσ_8$ datasets. We will also explain in details the predictions of the model on the late time behavior of the universe and compare the result with $Λ$CDM model. |
| title | Dark energy and a new realization of the matter Lagrangian |
| topic | General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics |
| url | https://arxiv.org/abs/2601.18825 |