English
Related papers

Related papers: A Cosmological Model without Singularity and Dark …

200 papers

We propose a mechanism of elementary thermal dark matter with mass up to $10^{14}$ GeV, within a standard cosmological history, whose relic abundance is determined solely by its interactions with the Standard Model, without violating the…

High Energy Physics - Phenomenology · Physics 2019-11-13 Hyungjin Kim , Eric Kuflik

Some problems of cosmology: the big bang singularity, the origin of conventional matter, of dark matter and of dark energy may be successfully described and treated in the framework of the Weyl-Dirac theory. This theory, being a minimal…

General Relativity and Quantum Cosmology · Physics 2013-08-07 Mark Israelit

We construct a cosmological model which is physically reasonable, mathematically tractable, and extends the study of CDM models to the case where the equations of state (EoS) for matter and dark energy (DE) vary with time. It is based on…

General Relativity and Quantum Cosmology · Physics 2012-06-14 J. Ponce de Leon

The small-scale structure problems of the universe can be solved by self-interacting dark matter that becomes strongly interacting at low energies. A particularly predictive model is resonant short-range self-interactions, with a…

High Energy Physics - Phenomenology · Physics 2019-05-14 Eric Braaten , Daekyoung Kang , Ranjan Laha

All presently known stellar-dynamical constraints on the size and mass of the supermassive compact dark object at the Galactic center are consistent with a ball of self-gravitating, nearly non-interacting, degenerate fermions with mass…

Astrophysics · Physics 2007-05-23 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

If space, time and mass-energy expand outward from the Big Bang along the time axis equally in the (+) and (-) directions, then time is symmetric by Weyl's definition. In the Feynman-Stueckelberg Interpretation, antimatter is identical to…

General Physics · Physics 2007-05-23 Trevor Pitts

It is shown that the cosmological constant links the roots both of General Relativity and Newtonian gravity via the general function satisfying Newton's theorem according to which the gravitating sphere acts as a point mass situated in its…

General Relativity and Quantum Cosmology · Physics 2019-01-10 V. G. Gurzadyan

We propose a possible resolution to the cosmological constant problem through a scenario in which the universe is composed of three components: matter, radiation (CMB) and vacuum energy such that vacuum energy is not constant and is…

General Relativity and Quantum Cosmology · Physics 2014-06-05 S. Zeynizadeh , M. Nouri-Zonoz

The cosmic large scale structure encodes the formation and evolution of a weblike network of dark matter and galaxies within the Universe. The cosmological information is wrapped up in non-Gaussian statistics requiring characterisation…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-26 Alex Gough

Since the geometry of our universe seems to depend very little on baryonic matter, we consider a variational principle involving only dark matter and dark energy which in addition make them depend on each other. There are no adjustable…

General Relativity and Quantum Cosmology · Physics 2013-11-19 Joseph Katz

In the standard FRW formalism, the scale factor is assumed to describe the expansion of the universe. However, by examining empty space with a positive cosmological constant (i.e., a de Sitter space), we find that this assumption is…

General Physics · Physics 2025-08-05 J. M. Greben

We generalize tensor-scalar theories of gravitation by the introduction of an abnormally weighting type of energy. This theory of tensor-scalar anomalous gravity is based on a relaxation of the weak equivalence principle that is now…

Astrophysics · Physics 2009-01-14 J. -M. Alimi , A. Füzfa

The Universe is modeled as consisting of pressureless baryonic matter and a bulk viscous fluid which is supposed to represent a unified description of the dark sector. In the homogeneous and isotropic background the \textit{total} energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-22 W. Zimdahl , H. E. S. Velten , W. S. Hipólito-Ricaldi

We extend mass scale sequence to a mass tree. From mass tree, the evolution of the universe is described by three stages: chaos, inflation and expansion. The first two stages have c mutations and the inflation appears as a step by step…

General Physics · Physics 2020-05-06 Wuliang Huang , Xiaodong Huang

Collisionless particles, such as cold dark matter, interact only by gravity and do not have any associated length scale, therefore the dark halos of galaxies should have negligible core radii. This expectation has been supported by…

Astrophysics · Physics 2009-09-25 Ben Moore

Mirror matter is a stable self-collisional dark matter candidate. If exact mirror parity is a conserved symmetry of nature, there could exist a parallel hidden (mirror) sector of the Universe which has the same kind of particles and the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Paolo Ciarcelluti

The large scale structure of the present Universe is determined by the growth of dark matter density fluctuations and by the dynamical action of dark energy and dark matter. While much progress has been made in recent years in constraining…

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

Here, creation of the universe is obtained only from gravity sector. The dynamical universe begins with two basic ingredients (i) vacuum energy, also called dark energy (as vacuum energy is not observed) and (ii) background radiation. These…

High Energy Physics - Theory · Physics 2007-05-23 S. K. Srivastava

There is now strong evidence that the main contribution to the cosmic energy density is not due to matter, but to another component with negative pressure. Its nature is still unknown: it could be the vacuum energy, manifesting itself as a…

Astrophysics · Physics 2007-05-23 Alberto Cappi