Related papers: Emulating $\Lambda$CDM-like expansion on the Phant…
Using N-body simulations, we measure the power spectrum of the effective dark matter density field, which is defined through the modified Poisson equation in $f(R)$ cosmologies. We find that when compared to the conventional dark matter…
Using some supernovae and CMB data, we constrain the Cardassian, Randall-Sundrum, and Dvali-Gabadadze-Porrati brane-inspired cosmological models. We show that a transient acceleration and an early loitering period are usually excluded by…
We investigate a brane model based on Randall-Sundrum scenarios with a generic dark energy component. The latter drives the accelerated expansion at late times of the Universe. In this scheme, extra terms are added into Einstein Field…
In this paper, the holographic dark energy model is considered in Brans-Dicke theory where the holographic dark energy density $\rho_{\Lambda} =3c^2 M^{2}_{pl} L^{-2}$ is replaced with $\rho_{h}=3c^2 \Phi(t)L^{-2}$. Here…
A fundamental question in cosmology is whether dark energy evolves over time, a topic that has gained prominence since the discovery of cosmic acceleration. Recently, the DESI collaboration has reported increasing evidence for evolving dark…
We present a comprehensive analysis of the cosmological implications of the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2) Lyman-$\alpha$ forest baryon acoustic oscillation (BAO) measurements, combined with DESI DR2 galaxy…
In the present work we have studied some features of the generalized Brans-Dicke (BD) model in which the scalar field is allowed to couple non-minimally with matter sector. Extended holographic Ricci dark energy (EHRDE) has been considered…
Early dark energy (EDE) is an extension to the $\Lambda$CDM model, proposed to reduce the tension between the measurements of the Hubble constant $H_0$ from the cosmic microwave background (CMB) and from the local cosmic distance ladder.…
The $\Lambda$CDM model successfully explains a wide range of cosmological observations; however, persistent discrepancies most notably the $H_0$ tension between early and late time measurements challenge its completeness. No proposed…
We argue that dark energy with multiple fields is theoretically well-motivated and predicts distinct observational signatures, in particular when cosmic acceleration takes place along a trajectory that is highly non-geodesic in field space.…
In the last decades, a cosmological model that fits observations through a vast range of scales emerged. It goes under the name of ${\Lambda}$CDM. However, there are still challenging questions that remain unanswered by this model, such as…
Recent observations from the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2) have revealed compelling evidence for dynamical dark energy, challenging the $\Lambda$CDM paradigm. In this work, we adopt a data-driven,…
The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…
In this study we analyze Type Ia supernovae (SNe Ia) data sourced from the Pantheon+ compilation to investigate late-time physics effects influencing the expansion history, $H(z)$, at redshifts $(z < 2)$. Our focus centers on a time-varying…
By finding the spinor eigenvalues for a single deficit angle (d-2)-sphere, we derive the radial potential for fermions on a d-dimensional black hole background that is embedded on a codimension two brane with conical singularity, where the…
We investigate the behaviour of dark energy using the recently released supernova data of Riess et al ~(2004) and a model independent parameterization for dark energy (DE). We find that, if no priors are imposed on $\Omega_{0m}$ and $h$, DE…
We describe the late-time acceleration of the Universe within the paradigm of the brane-world scenario. More precisely, we show how a phantom-like behaviour or a crossing of the cosmological constant line can be achieved safely in a…
In arXiv:2505.18900 it was claimed that an apparent evolution of the dark energy equation of state occurs within the standard $\Lambda$CDM cosmological model. I point out that this erroneous conclusion is due to a mathematical error.
In this letter, we show that in a particular braneworld scenario with variable brane tension, we obtain matter acting as dark energy while the gravitational constant $G$ promoted to a scalar field on the brane plays the role of matter (both…
Constraining simultaneously the Dark Energy(DE) equation of state and the curvature of the Universe is difficult due to strong degeneracies. To circumvent this problem when analyzing data it is usual to assume flatness to constrain DE, or…