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Related papers: Dark matter from torsion in Friedmann cosmology

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We investigate the background dynamics when dark energy is coupled to dark matter in the universe described by Einstein cosmology and Loop Quantum Cosmology. We introduce a new general form of dark sector coupling, which presents us a more…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Songbai Chen , Bin Wang , Jiliang Jing

In this work, we investigate non-interacting holographic dark energy (HDE) with the Hubble radius as the infrared cutoff in Einstein-Cartan gravity. We derive the Einstein-Cartan equations from the action principle and obtain Friedmann-like…

General Relativity and Quantum Cosmology · Physics 2026-05-22 Yongjun Yun , Jungjai Lee

An extension to the Einstein-Cartan (EC) action is discussed in terms of cosmological solutions. The torsion incorporated in the EC Lagrangian is assumed to be totally anti-symmetric, represented by a time-like axial vector $S^\mu$. The…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 David Benisty , Eduardo I. Guendelman , Armin van de Venn , David Vasak , Jürgen Struckmeier , Horst Stoecker

We study gravity coupled to scalar and fermion fields in the Einstein-Cartan framework. We discuss the most general form of the action that contains terms of mass dimension not bigger than four, leaving out only contributions quadratic in…

High Energy Physics - Theory · Physics 2021-08-17 Mikhail Shaposhnikov , Andrey Shkerin , Inar Timiryasov , Sebastian Zell

In view of late-time cosmic acceleration, a dark energy cosmological model is revisited wherein Einstein's cosmological constant is considered as a candidate of dark energy. Exact solution of Einstein field equations (EFEs) is derived in a…

General Relativity and Quantum Cosmology · Physics 2019-11-22 S. K. J. Pacif , Md Salahuddin Khan , L. K. Paikroy , Shalini Singh

We reconsider the entropic-force model in which both kind of Hubble terms ${\dot H}$ and $H^{2}$ appear in the effective dark energy (DE) density affecting the evolution of the main cosmological functions, namely the scale factor,…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-16 Spyros Basilakos , Joan Sola

We consider a recently proposed model in which dark matter interacts with a thermal background of dark radiation. Dark radiation consists of relativistic degrees of freedom which allow larger values of the expansion rate of the universe…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-24 Manuel A. Buen-Abad , Martin Schmaltz , Julien Lesgourgues , Thejs Brinckmann

We study the coupled dark energy model constructed from the general conformal transformation in which the coefficient of the conformal transformation depends on both the scalar field and its kinetic term. Under this conformal…

General Relativity and Quantum Cosmology · Physics 2022-04-12 Wittaya Thipaksorn , Stharporn Sapa , Khamphee Karwan

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

We study the collider, astrophysical and cosmological constraints on the dark matter sector of a conformal model within the framework of both the freeze out as well as the freeze in mechanism. The model has a dark sector with strong self…

High Energy Physics - Phenomenology · Physics 2019-12-25 Prasenjit Sanyal , Alekha C. Nayak , Gopal Kashyap , Pankaj Jain

The Covariant Canonical Gauge theory of Gravity (CCGG) is a gauge field formulation of gravity which a priori includes non-metricity and torsion. It extends the Lagrangian of Einstein's theory of general relativity by terms at least…

General Relativity and Quantum Cosmology · Physics 2023-04-13 Armin van de Venn , David Vasak , Johannes Kirsch , Jürgen Struckmeier

This paper deals with the symmetry analysis of the Einstein Cartan theory which is an extension of the General Relativity and it accounts for the space-time torsion. We begin by applying Noether Theorem to the Lagrangian of the FRW type…

General Relativity and Quantum Cosmology · Physics 2021-10-20 Ramkumar Radhakrishnan

The dark side of the universe is mysterious and its nature is still unknown. In fact, this poses perhaps as the biggest challenge in the modern cosmology. The two components of the dark sector (dark matter and dark energy) correspond today…

General Relativity and Quantum Cosmology · Physics 2017-02-21 Ricardo C. G. Landim

We investigate torsion-driven cosmological dynamics within the framework of Einstein-Cartan gravity using the De Donder-Weyl Hamiltonian formalism, where the tetrad and Lorentz connection act as independent variables and the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2026-02-18 Aarav Shah , M. Yu. Khlopov , M. Krasnov

Based on superfluid behavior of a (boson) dark matter as the light itself, a unified model for dark matter and quintessence is proposed. Inspired by (O'Dell et al. 2000) which in an exciting study showed that particular configurations of…

General Physics · Physics 2007-05-23 Reza Dastvan

A dark matter halo model is developed postulating a new state of matter, entities which have internal spin-like terms. Their motion in an external Schwarzschild metric is discussed. The internal spin motion contributes to the centrifugal…

General Physics · Physics 2017-05-25 H. L. Helfer

The accelerated expansion of the universe demands presence of an exotic matter, namely the dark energy. Though the cosmological constant fits this role very well, a scalar field minimally coupled to gravity, or quintessence, can also be…

General Relativity and Quantum Cosmology · Physics 2021-12-09 Dipayan Mukherjee , H. K. Jassal , Kinjalk Lochan

The Hubble tension is analyzed in the framework of quantum cosmological approach. It is found that there arises a new summand in the expression for the total energy density stipulated by the quantum Bohm potential. This additional energy…

General Relativity and Quantum Cosmology · Physics 2024-02-13 V. E. Kuzmichev , V. V. Kuzmichev

The bulk of recent cosmological research has focused on the adiabatic cold dark matter model and its simple extensions. Here we present an accurate fitting formula that describes the matter transfer functions of all common variants,…

Astrophysics · Physics 2009-10-30 Daniel J. Eisenstein , Wayne Hu
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