تقرير
Testing a varying-$\Lambda$ model for dark energy within Co-varying Physical Couplings framework
| العنوان: | Testing a varying-$\Lambda$ model for dark energy within Co-varying Physical Couplings framework |
|---|---|
| المؤلفون: | Cuzinatto, R. R., Gupta, R. P., Holanda, R. F. L., Jesus, J. F., Pereira, S. H. |
| المصدر: | MNRAS 515, 5981-5992 (2022) |
| سنة النشر: | 2022 |
| المجموعة: | Astrophysics General Relativity and Quantum Cosmology |
| مصطلحات موضوعية: | General Relativity and Quantum Cosmology, Astrophysics - Cosmology and Nongalactic Astrophysics |
| الوصف: | The Co-varying Physical Couplings (CPC) framework is a modified gravity set up assuming Einstein Field Equations wherein the quantities $\{G,c,\Lambda\}$ are promoted to space-time functions. Bianchi identity and the requirement of stress-energy tensor conservation entangle the possible variations of the couplings $\{G,c,\Lambda\}$, which are forced to co-vary as dictated by the General Constraint (GC). In this paper we explore a cosmological model wherein $G$, $c$ and $\Lambda$ are functions of the redshift respecting the GC of the CPC framework. We assume a linear parametrization of $\Lambda$ in terms of the scale factor $a$. We use the ansatz $\dot{G}/G = \sigma \left( \dot{c}/c \right)$ with $\sigma =$ constant to deduce the functional forms of $c=c(z)$ and $G=G(z)$. We show that this varying-$\{G,c,\Lambda\}$ model fits SNe Ia data and $H(z)$ data with $\sigma = 3$. The model parameters can be constrained to describe dark energy at the background level. Comment: 14 pages plus references and figures; v2: matches the published version |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1093/mnras/stac2039 |
| URL الوصول: | http://arxiv.org/abs/2204.10764 |
| رقم الأكسشن: | edsarx.2204.10764 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1093/mnras/stac2039 |
|---|