scholarly journals Dark Matter and Dark Energy in the Universe

2018 ◽  
Vol 14 (1) ◽  
pp. 5292-5295
Author(s):  
Yuanjie Li ◽  
Lihong Zhang ◽  
Peng Dong
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Dark Energy ◽  
Early Universe ◽  
Left Behind ◽  
Time Quantum ◽  
The Universe

This paper points out that not only all quantum-ghost puzzles occur in the Time Quantum Worm Hole, but also the dark matter in the universe is hidden in it. Dark energy is the contribution of the Planck black hole left behind by the early universe.

scholarly journals ACCELERATION AND DECELERATION IN THE CURVATURE-INDUCED PHANTOM MODEL OF THE LATE AND FUTURE UNIVERSE: COSMIC COLLAPSE AND ITS QUANTUM ESCAPE

2009 ◽  
Vol 18 (05) ◽  
pp. 865-887
Author(s):  
S. K. SRIVASTAVA ◽  
J. DUTTA
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Quantum Gravity ◽  
Cosmological Constant ◽  
Early Universe ◽  
High Energy ◽  
High Energy Density ◽  
Energy Models ◽  
Acceleration And Deceleration ◽  
The Universe

In this paper, the cosmology of the late and future universe is obtained from f(R) gravity with nonlinear curvature terms R2 and R3 (R is the Ricci scalar curvature). It is different from f(R) dark energy models where nonlinear curvature terms are taken as a gravitational alternative to dark energy. In the present model, neither linear nor nonlinear curvature terms are taken as dark energy. Rather, dark energy terms are induced by curvature terms and appear in the Friedmann equation derived from f(R) gravitational equations. This approach has an advantage over f(R) dark energy models in three ways: (i) results are consistent with WMAP observations, (ii) dark matter is produced from the gravitational sector and (iii) the universe expands as ~ t2/3 during dominance of the curvature-induced dark matter, which is consistent with the standard cosmology. Curvature-induced dark energy mimics phantom and causes late acceleration. It is found that transition from matter-driven deceleration to acceleration takes place at the redshift 0.36 at time 0.59 t0 (t0 is the present age of the universe). Different phases of this model, including acceleration and deceleration during the phantom phase, are investigated. It is found that expansion of the universe will stop at the age of 3.87 t0 + 694.4 kyr. After this epoch, the universe will contract and collapse by the time of 336.87 t0 + 694.4 kyr. Further, it is shown that cosmic collapse obtained from classical mechanics can be avoided by making quantum gravity corrections relevant near the collapse time due to extremely high energy density and large curvature analogous to the state of the very early universe. Interestingly, the cosmological constant is also induced here; it is extremely small in the classical domain but becomes very high in the quantum domain. This result explains the largeness of the cosmological constant in the early universe due to quantum gravity effects during this era and its very low value in the present universe due to negligible quantum effect in the late universe.

scholarly journals On the Fundamental Particles and Reactions of Nature

2021 ◽  
Author(s):  
Jian-Bin Bao ◽  
Nicholas P. Bao
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Dark Energy ◽  
Dynamic Equilibrium ◽  
Big Bang ◽  
Observable Universe ◽  
White Hole ◽  
Fundamental Particles ◽  
Degeneracy Pressure ◽  
The Universe

There are unsolved problems related to inflation, gravity, dark matter, dark energy, missing antimatter, and the birth of the universe. Some of them can be better answered by assuming the existence of aether and hypoatoms. Both were created during the inflation in the very early universe. While aether forms vacuum, hypoatoms, composed of both matter and antimatter and believed to be neutrinos, form all observable matter. In vacuum, aether exists between the particle-antiparticle dark matter form and the dark energy form in a dynamic equilibrium: A + A-bar = gamma + gamma. The same reaction stabilizes hypoatoms and generates a 3-dimensional sink flow of aether that causes gravity. Based on the hypoatom structure, the singularity does not exist inside a black hole; the core of the black hole is a hypoatom star or neutrino star. By gaining enough mass, ca. 3 X 1022 Msun, to exceed neutrino degeneracy pressure, the black hole collapses or annihilates into the singularity, thus turning itself into a white hole or a Big Bang. The universe is anisotropic and nonhomogeneous. Its center, or where the Big Bang happened, is at about 0.671 times the radius of the observable universe at the Galactic coordinates (l, b) ~ (286°, -42°). If we look from the Earth to the center of the universe, the universe is rotating clockwise.

Inflation, dark matter, and dark energy

2019 ◽  
pp. 423-464
Author(s):  
Malcolm S. Longair ◽  
Chris Smeenk
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Power Spectrum ◽  
Early Universe ◽  
Particle Physics ◽  
Large Scale ◽  
Initial State ◽  
Large Scale Structures ◽  
Initial Power ◽  
The Universe

The success of the ΛCDM model has raised a number of challenging problems for the origin of structure in the universe and the initial state from which it evolved. The origins of these basic cosmological problems are described. The dark matter must be non-baryonic, but its nature has not been established. Likewise, the nature of the dark energy is not understood. The inflationary model for the very early universe has had some undoubted successes in accounting for the initial power-spectrum of fluctuations from which large-scale structures formed but there is no physical realization of the inflaton field. Defects formed during phase transitions in the early universe cannot account for the initial power spectrum of fluctuations, but may have some part to play in structure formation. The origin of the baryon-antibaryon asymmetry in the early universe is not understood in terms of theories of particle physics.

scholarly journals Displaced new physics at colliders and the early universe before its first second

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Lorenzo Calibbi ◽  
Francesco D’Eramo ◽  
Sam Junius ◽  
Laura Lopez-Honorez ◽  
Alberto Mariotti
Keyword(s):  
Dark Matter ◽  
Early Universe ◽  
Upper Bound ◽  
New Physics ◽  
Early History ◽  
Relic Density ◽  
History Of ◽  
Indirect Information ◽  
The Universe

Abstract Displaced vertices at colliders, arising from the production and decay of long-lived particles, probe dark matter candidates produced via freeze-in. If one assumes a standard cosmological history, these decays happen inside the detector only if the dark matter is very light because of the relic density constraint. Here, we argue how displaced events could very well point to freeze-in within a non-standard early universe history. Focusing on the cosmology of inflationary reheating, we explore the interplay between the reheating temperature and collider signatures for minimal freeze-in scenarios. Observing displaced events at the LHC would allow to set an upper bound on the reheating temperature and, in general, to gather indirect information on the early history of the universe.

scholarly journals INTERACTION BETWEEN DARK ENERGY AND DARK MATTER: OBSERVATIONAL CONSTRAINTS FROM OHD, BAO, CMB AND SNe Ia

2013 ◽  
Vol 22 (14) ◽  
pp. 1350082 ◽  
Author(s):  
SHUO CAO ◽  
NAN LIANG
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Observational Constraints ◽  
Coincidence Problem ◽  
Cosmological Constraints ◽  
Coincidence Index ◽  
Acceleration Of The Universe ◽  
Interaction Term ◽  
Negative Coupling ◽  
The Universe

In order to test if there is energy transfer between dark energy (DE) and dark matter (DM), we investigate cosmological constraints on two forms of nontrivial interaction between the DM sector and the sector responsible for the acceleration of the universe, in light of the newly revised observations including OHD, CMB, BAO and SNe Ia. More precisely, we find the same tendencies for both phenomenological forms of the interaction term Q = 3γHρ, i.e. the parameter γ to be a small number, |γ| ≈ 10-2. However, concerning the sign of the interaction parameter, we observe that γ > 0 when the interaction between dark sectors is proportional to the energy density of dust matter, whereas the negative coupling (γ < 0) is preferred by observations when the interaction term is proportional to DE density. We further discuss two possible explanations to this incompatibility and apply a quantitative criteria to judge the severity of the coincidence problem. Results suggest that the γm IDE model with a positive coupling may alleviate the coincidence problem, since its coincidence index C is smaller than that for the γd IDE model, the interacting quintessence and phantom models by four orders of magnitude.

scholarly journals On The Symmetry of The Universe

2020 ◽  
Author(s):  
Engel Roza
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Thermodynamic Equilibrium ◽  
Vacuum Energy ◽  
Quantum Mechanical ◽  
Baryonic Matter ◽  
Time Uncertainty ◽  
Matter Effect ◽  
Mechanical Interpretation ◽  
The Universe

It is shown that the Lambda component in the cosmological Lambda-CDM model can be conceived as vacuum energy, consisting of gravitational particles subject to Heisenberg&rsquo;s energy-time uncertainty. These particles can be modelled as elementary polarisable Dirac-type dipoles (&ldquo;darks&rdquo;) in a fluidal space at thermodynamic equilibrium, with spins that are subject to the Bekenstein-Hawking entropy. Around the baryonic kernels, uniformly distributed in the universe, the spins are polarized, thereby invoking an increase of the effective gravitational strength of the kernels. It explains the dark matter effect to the extent that the numerical value of Milgrom&rsquo;s acceleration constant can be assessed by theory. Non-polarized vacuum particles beyond the baryonic kernels compose the dark energy. The result is a quantum mechanical interpretation of gravity in terms of quantitatively established shares in baryonic matter, dark matter and dark energy, which correspond with the values of the Lambda-CDM model..

Using Lorentz Violation for Early Universe GW Generation Due to Black Hole Destruction in the Early Universe as by Freeze

2021 ◽  
Author(s):  
Andrew W Beckwith
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Dark Energy ◽  
Early Universe ◽  
Physical Mechanism ◽  
Lorentz Violation ◽  
Graviton Mass ◽  
Work Done ◽  
Momentum Relation

We are using information from a paper deriving a Lorentz-violating energy-momentum relation entailing an exact mo_mentum cutof as stated by G. Salesi . Salesi in his work allegedly defines Pre Planckian physics, whereas we restrict our given application to GW generation and DE formation in the first 10^-39s to 10^-33s or so seconds in the early universe. This procedure is inacted due to an earlier work whereas referees exhibited puzzlement as to the physical mechanism for release of Gravitons in the very early universe. The calculation is meant to be complementary to work done in the Book &ldquo;Dark Energy&rdquo; by M. Li, X-D. Li, and Y. Wang, and also a calculation for Black hole destruction as outlined by Karen Freeze, et. al. The GW generation will be when there is sufficient early universe density so as to break apart Relic Black holes but we claim that this destruction is directly linked to a Lorentz violating energy-momentum G. Salesi derived, which we adopt, with a mass m added in the G. Salesi energy momentum results proportional to a tiny graviton mass, times the number of gravitons in the first 10^-43 seconds

Most of the Universe is Missing!

2019 ◽  
pp. 64-72
Author(s):  
Nicholas Mee
Keyword(s):  
Dark Matter ◽  
Galaxy Clusters ◽  
Early Universe ◽  
The World ◽  
Unknown Form ◽  
Theory Of Gravity ◽  
Stable Particles ◽  
The Universe

Most of the matter in the universe exists in an unknown form called dark matter. All estimates of the mass of galaxies and galaxy clusters suggest they contain far more matter than is visible to us in the form of stars. Conventional explanations, such as the existence of large quantities of burnt-out stars known as MACHOs or dark gas clouds, have been ruled out. The most popular explanation is that dark matter consists of vast quantities of hypothetical stable particles known as WIMPs that were produced in vast quantities in the very early universe. Many laboratories around the world are searching for signs of these particles. These include the Italian Gran Sasso laboratory running the XENON100 experiment. Some theorists have suggested the evidence for dark matter would disappear if we had a better theory of gravity. Analysis of the Bullet Cluster indicates such proposals will not work.

scholarly journals Observational constraints of a new unified dark fluid and the H0 tension

2019 ◽  
Vol 490 (2) ◽  
pp. 2071-2085 ◽  
Author(s):  
Weiqiang Yang ◽  
Supriya Pan ◽  
Andronikos Paliathanasis ◽  
Subir Ghosh ◽  
Yabo Wu
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Large Scale ◽  
Cold Dark Matter ◽  
Early Time ◽  
Observational Constraints ◽  
Minimal Extension ◽  
Energy Evolution ◽  
The Universe ◽  
Different Sources

ABSTRACT Unified cosmological models have received a lot of attention in astrophysics community for explaining both the dark matter and dark energy evolution. The Chaplygin cosmologies, a well-known name in this group have been investigated matched with observations from different sources. Obviously, Chaplygin cosmologies have to obey restrictions in order to be consistent with the observational data. As a consequence, alternative unified models, differing from Chaplygin model, are of special interest. In the present work, we consider a specific example of such a unified cosmological model, that is quantified by only a single parameter μ, that can be considered as a minimal extension of the Λ-cold dark matter cosmology. We investigate its observational boundaries together with an analysis of the universe at large scale. Our study shows that at early time the model behaves like a dust, and as time evolves, it mimics a dark energy fluid depicting a clear transition from the early decelerating phase to the late cosmic accelerating phase. Finally, the model approaches the cosmological constant boundary in an asymptotic manner. We remark that for the present unified model, the estimations of H0 are slightly higher than its local estimation and thus alleviating the H0 tension.

scholarly journals Do we come from a quantum anomaly?

2019 ◽  
Vol 28 (14) ◽  
pp. 1944002 ◽  
Author(s):  
Spyros Basilakos ◽  
Nick E. Mavromatos ◽  
Joan Solà Peracaula
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Energy Density ◽  
Hubble Parameter ◽  
Vacuum Energy ◽  
Vacuum Energy Density ◽  
Quantum Anomaly ◽  
Inflationary Phase ◽  
Axion Field ◽  
The Universe

We present a string-based picture of the cosmological evolution in which (CP-violating) gravitational anomalies acting during the inflationary phase of the universe cause the vacuum energy density to “run” with the effective Hubble parameter squared, [Formula: see text], thanks to the axion field of the bosonic string multiplet. This leads to baryogenesis through leptogenesis with massive right-handed neutrinos. The generation of chiral matter after inflation helps in cancelling the anomalies in the observable radiation- and matter-dominated eras. The present era inherits the same “running vacuum” structure triggered during the inflationary time by the axion field. The current dark energy is thus predicted to be mildly dynamical, and dark matter should be made of axions. Paraphrasing Carl Sagan [ https://www.goodreads.com/author/quotes/10538.Carl_Sagan .]: we are all anomalously made from starstuff.

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