37 citations · 129 across the 25 of their papers we have counts for
15 papers · 1 filter
Study of dynamical systems and large-scale structure
Dumiso Mithi, Saikat Charkraborty, Shambel Sahlu +1
In this study, we employ dynamical systems methods to analyse the large-scale structure by considering two distinct interaction models (linear and non-linear) within the dark secto…
Constraining the modified symmetric teleparallel gravity using cosmological data
Shambel Sahlu, Amare Abebe
This paper examines the late-time accelerating Universe and the formation of large-scale structures within the modified symmetric teleparallel gravity framework, specifically using…
Viscous cosmological fluids and large-scale structure
BG Mbewe, RR Mekuria, S Sahlu +1
In this paper, we study the viscous fluid cosmological model that when certain conditions are invoked mimics the CDM model. The background equations governing the evolution of v…
Quintessence phase of the late-time Universe in gravity
Shambel Sahlu, Bhupendra Kumar Shukla, Rishi Kumar Tiwari +2
In this paper, we have studied the late-time accelerating expansion of the Universe using the matter-geometry coupled gravity model, where is the non-metricity sc…
Constraining viscous fluid models in gravity with data
Shambel Sahlu, Renier T. Hough, Amare Abebe +1
We investigate the impact of bulk viscosity on the accelerating expansion and large-scale structure formation of a Universe in which the underlying gravitational interaction is des…
Structure growth in cosmology
Shambel Sahlu, Álvaro de la Cruz-Dombriz, Amare Abebe
We take into account redshift-space distortion measurements to investigate the growth of cosmological large-scale structures within the framework of modified symmetric teleparallel…
Linear Cosmological perturbations in Gravity
Shambel Sahlu, Endalkachew Tsegaye
In this manuscript, we studied the accelerated expansion history of the universe and the formations of large-scale structures using gravity model. The expansion rate of the…
Confronting the Chaplygin gas with data: background and perturbed cosmic dynamics
Shambel Sahlu, Heba Sami, Renier Hough +3
In this paper, we undertake a unified study of background dynamics and cosmological perturbations in the presence of the Chaplygin gas. This is done by first constraining the backg…
Covariant density and velocity perturbations of the quasi-Newtonian cosmological model in gravity
Heba Sami, Shambel Sahlu, Amare Abebe +1
We investigate classes of shear-free cosmological dust models with irrotational fluid flows within the framework of gravity. In particular, we use the covariant form…
On multifluid perturbations in scalar-tensor cosmology
Joseph Ntahompagaze, Shambel Sahlu, Amare Abebe +1
In this paper the scalar-tensor theory is applied to the study of perturbations in a multi-fluid universe, using the 1+3 covariant approach. Both scalar and harmonic decompositions…
Perturbations in a Chaplygin gas Cosmology
Shambel Sahlu, Heba Sami, Anna-Mia Swart +3
In this paper we study the perturbations of a cosmic multi-fluid medium consisting of radiation, dust and a Chaplygin gas. To do so, we follow the 1 + 3 covariant formalism and der…
Accelerating universe in modified teleparallel gravity theory
Shambel Sahlu, Joseph Ntahompagaze, Amare Abebe +1
This paper studies the cosmology of accelerating expansion of the universe in modified teleparallel gravity theory. We discuss the cosmology of gravity theory and its impl…
Scalar perturbations in gravity using the covariant approach
Shambel Sahlu, Joseph Ntahompagaze, Amare Abebe +2
The cosmological scalar perturbations of standard matter are investigated in the context of extended teleparallel gravity theories using the covariant formalism. After…
The Chaplygin gas as a model for modified teleparallel gravity?
Shambel Sahlu, Joseph Ntahompagaze, Maye Elmardi +1
This paper explores the possibility of treating the exotic Chaplygin-gas (CG) fluid model as some manifestation of an gravitation. To this end, we use the different cosmolog…
Inflation constraints for classes of f(R) models
Joseph Ntahompagaze, Jean Damascene Mbarubukeye, Shambel Sahlu +1
In this paper, we explore the equivalence between two theories, namely f(R) and scalar-tensor theories of gravity. We use this equivalence to explore several f(R) toy models focusi…