Viscous cosmology for early-and late-time universe

I Brevik, Ø Grøn, J de Haro, SD Odintsov… - International Journal of …, 2017 - World Scientific
From a hydrodynamicist's point of view the inclusion of viscosity concepts in the macroscopic
theory of the cosmic fluid would appear most natural, as an ideal fluid is after all an …

Recent advances in cosmological singularities

O Trivedi - Symmetry, 2024 - mdpi.com
The discovery of the Universe's late-time acceleration and dark energy has led to a great
deal of research into cosmological singularities, and in this brief review, we discuss all the …

Inflationary universe from perfect fluid and gravity and its comparison with observational data

K Bamba, S Nojiri, SD Odintsov, D Saez-Gomez - Physical Review D, 2014 - APS
We investigate the descriptions for the observables of inflationary models, in particular, the
spectral index of curvature perturbations, the tensor-to-scalar ratio, and the running of the …

[HTML][HTML] Late-time constraints on barotropic fluid cosmology

S Mandal, A Singh, R Chaubey - Physics Letters A, 2024 - Elsevier
We investigate the cosmological implications of the Friedmann-Robertson-Walker (FRW)
model having a flat-spatial section with barotropic fluid. We examine the resulting …

Cosmic dynamics with late-time constraints on the parametric deceleration parameter model

AR Lalke, GP Singh, A Singh - The European Physical Journal Plus, 2024 - Springer
We investigate the evolution of a flat Friedmann–Lemaitre–Robertson–Walker (FLRW)
model equipped with the matter content induced by the fluid having equation of state …

Lagrangian formulation and implications of barotropic fluid cosmologies

A Singh, R Raushan, R Chaubey, S Mandal… - … Journal of Geometric …, 2022 - World Scientific
In this paper, we investigate the behavior of cosmologies in homogeneous and isotropic
background with a barotropic fluid. We solve the continuity equation and study several …

Revisiting fractional cosmology

B Micolta-Riascos, AD Millano, G Leon, C Erices… - Fractal and …, 2023 - mdpi.com
Recently, the research community has been exploring fractional calculus to address
problems related to cosmology; in this approach, the gravitational action integral is altered …

Cosmic dynamics of isotropic models with inhomogeneous EoS: A dynamical system perspective

A Singh, AK Shukla, S Krishnannair - International Journal of …, 2023 - World Scientific
We examine the homogeneous and isotropic models sourced by the fluid having an
inhomogenous equation of state (EoS) using qualitative methods. The flat Friedmann …

Finite-time singularities in swampland-related dark-energy models

SD Odintsov, VK Oikonomou - Europhysics Letters, 2019 - iopscience.iop.org
In this work we shall investigate the singularity structure of the phase space corresponding
to an exponential quintessence dark-energy model recently related to swampland models …

Cosmological singularities in gravity

O Trivedi, M Khlopov, JL Said, R Nunes - The European Physical Journal …, 2023 - Springer
The pursuit of understanding the mysteries surrounding dark energy has sparked significant
interest within the field of cosmology. While conventional approaches, such as the …