Dark Matter in the Universe

Thirty years ago, observational cosmology consisted of the search for two numbers: Ho, the rate of expansion of the universe at the position of the Galaxy; and qo, the deceleration parameter. Twenty years ago, the discovery of the relic radiation from the Big Bang produced another number, 3oK. But it is the past decade which has seen the enormous development in both observational and theoretical cosmology. The universe is known to be immeasurably richer and more varied than we had thought. There is growing acceptance of a universe in which most of the matter is not luminous. Nature has played a trick on astronomers, for we thought we were studying the universe. We now know that we were studying only the small fraction of it that is luminous. I suspect that this talk this evening is the first IAU Discourse devoted to something that astronomers cannot see at any wavelength: Dark Matter in the Universe.

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Deuterium in the Galaxy

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000014910 ◽

1977 ◽

Vol 3 (2) ◽

pp. 100-101 ◽

Cited By ~ 1

Author(s):

R. D. Brown

Keyword(s):

Great Majority ◽

Big Bang ◽

Baryon Density ◽

The Galaxy ◽

Mass Fractions ◽

Expansion Of The Universe ◽

Sensitive Function ◽

The Big Bang ◽

Deuterium Production ◽

The Universe

There have been a number of attempts made in the last decade or two to observe deuterium in parts of the universe other than here in Earth. It is of interest merely to detect deuterium elsewhere just as it is to detect the occurrence of any nuclide. However in the case of deuterium there is a special interest because in big-bang cosmologies the great majority of deuterium in the universe is considered to have been formed in the initial fireball (Wagoner, 1973). Any observation of the present abundance of deuterium thus might give information about the very early stages of the creation of the universe. Detailed studies of nucleosynthesis during the early expansion of hot big-bang universes have however indicated a particular feature of deuterium production. (Fig. 1) The mass fraction produced X(D) is a very sensitive function of the size of the universe, as measured say by the present baryon density ϱb. Other nuclides that are mainly produced in the early expansion, such as 4He, have mass fractions less dependent on ϱb. Thus if we adopt the big-bang model for our universe we can determine ϱb from observations of X(D). Apart from any intrinsic interest in the present density of the’universe, there is considerable interest in whether the value is great enough for the present expansion to halt and go over to a collapse — or so small that the expansion of the universe will go on forever.

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A Physico-Chemical Approach To Understanding Cosmic Evolution: Thermodynamics Of Expansion And Composition Of The Universe

10.21203/rs.3.rs-306782/v1 ◽

2021 ◽

Author(s):

Carlos A. Melendres

Keyword(s):

Dark Matter ◽

Dark Energy ◽

State Parameter ◽

Big Bang ◽

Fundamental Particles ◽

Physico Chemical ◽

Expansion Of The Universe ◽

Cooling Phase ◽

The Big Bang ◽

The Universe

Abstract We present a physico-chemical approach towards understanding the mysteries associated with the Inflationary Big Bang model of Cosmic evolution based on a theory that space consists of energy quanta. We use thermodynamics to elucidate the expansion of the universe, its composition, and the nature of dark energy and dark matter. The universe started from an atomic size volume of space quanta at very high temperature. Upon expansion and cooling, phase transitions resulted in the formation of fundamental particles, and matter which grow into stars, galaxies, and clusters due to gravity. From cooling data on the universe, we constructed a thermodynamic phase diagram of composition of the universe, from which we obtained a correlation between dark energy and the energy of space. Using Friedmann’s equations, our Quantum Space model fitted well the WMAP data on cosmic composition with an equation of state parameter, w= -0.7. The expansion of the universe was adiabatic and decelerating during the first 7 billion years after the Big Bang. It accelerated due to the dominance of dark energy at 7.25 x 109 years, in good agreement with BOSS measurements. Dark Matter is identified as a plasma form of matter similar to that which existed before recombination and during reionization.

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Quantum Space and Thermodynamic Approach to Understanding Cosmic Evolution

10.20944/preprints201812.0357.v2 ◽

2020 ◽

Author(s):

Carlos Melendres

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Big Bang ◽

Cooling Curve ◽

Thermodynamic Approach ◽

Quantum Space ◽

Wave Particle Duality ◽

Expansion Of The Universe ◽

The Big Bang ◽

The Universe

We present a thermodynamic approach in modeling the evolution of the universe based on a theory that space consists of energy quanta, the spaceons. From wave-particle duality, they can be treated as an ideal gas. The model is similar to the Big Bang but without Inflation. It provides an insight into the nature of dark energy and dark matter, and an explanation for the accelerated expansion of the universe. The universe started from an atomic size volume of spaceons at very high temperature and pressure. Upon expansion and cooling, phase transitions occurred resulting in the formation of fundamental particles, and matter. These nucleate and grow into stars, galaxies, and clusters due to the action of gravity. From the cooling curve of the universe we constructed a thermodynamic phase diagram of cosmic composition, from which we obtained the correlation between dark energy and the energy of space. Using Friedmann’s equations, our model fits well the WMAP data on cosmic composition with an equation of state parameter, w= -0.7. The dominance of dark energy started at 7.25 x 109 years, in good agreement with BOSS measurements. The expansion of space is attributed to a scalar quantum space field. Dark Matter is identified as a plasma form of matter similar to that which existed during the photon epoch, prior to recombination. The thermodynamics of expansion of the universe was adiabatic and decelerating during the first 7 billion years after the Big Bang; it accelerated thereafter. A negative pressure for Dark Energy is required to sustain the latter. This is consistent with the theory of General Relativity and the law of conservation of energy. We propose a mechanism for the acceleration as due to consolidation of matter forming Dark Energy Stars (DES) and other compact objects. The resulting reduction in gravitational potential energy feeds back energy for the expansion. Space will continue to expand and dark energy will undergo phase transition to a Bose-Einstein condensate, a superfluid form of matter. Self-gravitation can cause a bounce and start a new Big Bang. We show how the interplay of gravitational and space forces leads to a cyclic, maybe eternal, universe.

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Dynamo effects in gravity

E3S Web of Conferences ◽

10.1051/e3sconf/201912702009 ◽

2019 ◽

Vol 127 ◽

pp. 02009

Author(s):

Boris Shevtsov

Keyword(s):

Gravitational Constant ◽

Nonlinear Oscillations ◽

Big Bang ◽

Baryon Asymmetry ◽

System Of Equations ◽

Fractal Structures ◽

Expansion Of The Universe ◽

The Big Bang ◽

The Universe ◽

Made In

Nonlinear oscillations in the dynamic system of gravitational and material fields are considered. The problems of singularities and caustics in gravity, expansion and baryon asymmetry of the Universe, wave prohibition of collapse into black holes, and failure of the Big Bang concept are discussed. It is assumed that the effects of the expansion of the Universe are coupling with the reverse collapse of dark matter. This hypothesis is used to substantiate the vortex and fractal structures in the distribution of matter. A system of equations is proposed for describing turbulent and fluctuation processes in gravitational and material fields. Estimates of the di usion parameters of such a system are made in comparison with the gravitational constant.

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Is the expansion of universe accelerating or the Photons decelerating?

International Journal of Advanced Astronomy ◽

10.14419/ijaa.v3i1.4531 ◽

2015 ◽

Vol 3 (1) ◽

pp. 40

Author(s):

Hasmukh Tank

Keyword(s):

Big Bang ◽

Time Dilation ◽

Red Shift ◽

Light Curves ◽

Accelerated Expansion ◽

Gravitational Acceleration ◽

Expansion Of The Universe ◽

Pi Mesons ◽

The Big Bang ◽

The Universe

Astronomical observations of the cosmological red-shift are currently interpreted in terms of ‘expansion of universe’ and ‘accelerated-expansion of the universe’, at the rate of H0 c; here H0 is Hubble’s constant, and c is the speed of light. Whereas a straight-forward derivation presented here suggests that: rather it is the photon which is decelerating, at the rate of H0 c. Such a deceleration of photons can be caused by virtual electrons, positrons and pi-mesons, contained in the extra galactic quantum vacuum, because: they do have gravitational-acceleration of the same order as H0 c at their “surfaces”; or by decay of a photon into a lighter photon and a particle of mass h H0 / c2. Tired-light interpretations of the cosmological red-shift’ were so far considered as not compatible with the observations of ‘time-dilation of super-novae light-curves’; so in a paper titled: “Wave-theoretical insight into the relativistic ‘length-contraction’ and ‘time-dilation of super-novae light-curves’” (Tank, Hasmukh K. 2013), it has been already shown that any mechanism which can cause ‘cosmological red-shift’ will also cause ‘time-dilation of super-novae light-curves’. Therefore, we now need not to remain confined to the Big-Bang model of cosmology.

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A classical non-quantum all-time time-symmetrical zero-energy single-bounce model for the creation, big bang, and death of the universe

International Journal of Modern Physics D ◽

10.1142/s0218271819440243 ◽

2019 ◽

Vol 28 (14) ◽

pp. 1944024 ◽

Cited By ~ 1

Author(s):

Arthur E. Fischer

Keyword(s):

Dark Matter ◽

Cold Dark Matter ◽

Big Bang ◽

Final States ◽

Level Curve ◽

Zero Energy ◽

Time Model ◽

Gravitational Effects ◽

The Big Bang ◽

The Universe

In this paper, we show how the [Formula: see text]CDM (Lambda Cold Dark Matter) Standard Model for cosmology can be extrapolated backwards through the big bang into the infinite past to yield an all-time model of the universe with scale factor given by [Formula: see text] defined and continuous for all [Formula: see text] and smooth ([Formula: see text] and satisfying Friedmann’s equation for all [Formula: see text]. At the big bang [Formula: see text], there is a nondifferentiable cusp singularity and our model shows some details of the behavior of the universe at this singularity. Our model is a zero-energy single-bounce model and an examination of the [Formula: see text]-plot of the [Formula: see text] level curve gives critical information about the initial and final states of the universe, about the evolution of the universe, and about the behavior of the universe at the big bang. Our results show that much can be said classically about the birth, big bang and death of the universe before one needs to reach for quantum gravitational effects.

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Big Bang Nucleosynthesis in Visible and Hidden-Mirror Sectors

Advances in High Energy Physics ◽

10.1155/2014/702343 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Paolo Ciarcelluti

Keyword(s):

Dark Matter ◽

Building Blocks ◽

Big Bang ◽

Dark Matter Candidate ◽

Big Bang Nucleosynthesis ◽

Enhanced Production ◽

The Standard Model ◽

The Big Bang ◽

The Universe ◽

Mirror Matter

One of the still viable candidates for the dark matter is the so-called mirror matter. Its cosmological and astrophysical implications were widely studied, pointing out the importance to go further with research. In particular, the Big Bang nucleosynthesis provides a strong test for every dark matter candidate, since it is well studied and involves relatively few free parameters. The necessity of accurate studies of primordial nucleosynthesis with mirror matter has then emerged. I present here the results of accurate numerical simulations of the primordial production of both ordinary nuclides and nuclides made of mirror baryons, in presence of a hidden mirror sector with unbroken parity symmetry and with gravitational interactions only. These elements are the building blocks of all the structures forming in the Universe; therefore, their chemical composition is a key ingredient for astrophysics with mirror dark matter. The production of ordinary nuclides shows differences from the standard model for a ratio of the temperatures between mirror and ordinary sectorsx=T′/T≳0.3, and they present an interesting decrease of the abundance ofLi7. For the mirror nuclides, instead, one observes an enhanced production ofHe4, which becomes the dominant element forx≲0.5, and much larger abundances of heavier elements.

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Charged Dark Matters and Extended Standard Model

10.20944/preprints201806.0225.v3 ◽

2018 ◽

Author(s):

Jae-Kwang Hwang

Keyword(s):

Dark Matter ◽

Vacuum Energy ◽

Three Dimensional ◽

Particle Creation ◽

Big Bang ◽

Strong Force ◽

Dark Matters ◽

The Big Bang ◽

The Universe ◽

Universe Evolution

The properties of the charged dark matters are discussed in terms of the new three-dimensional quantized space model. Because of the graviton evaporations, the very small Coulomb’s constant (k(dd)) of 10 −48 k and large gravitation constant (GN(dd)) of 106 GN for the charged dark matters at the present time are expected. The tentative values of G and k are used for the explanation purpose. Therefore, Fc(mm) > Fg(dd) > Fg(mm) > Fg(dm) > Fc(dd) > Fc(dm) = Fc(lq) = 0 for the proton-like particle. Also, the gravitation constant has been changed with increasing of the time because of the graviton evaporation. In the present work, the B1, B2 and B3 bastons with the condition of k(mm) = k >> k(dd) > k(dm) = 0 are explained as the good candidates of the dark matters. Also, the particle creation, dark matters and dark energy could be deeply associated with the changing gravitation constants (G). It is expected that the changing process of the gravitation constant between the matters from GN(mm) ≈ 1036 GN to GN(mm) = GN happened mostly near the inflation period. Therefore, during most of the universe evolution the gravitation constant could be taken as GN(mm) = GN. And the effective charges and effective rest masses of the particles are defined in terms of the fixed Coulomb’s constant (k) and fixed gravitation constant (GN). Then, the effective charge of the B1 dark matter with EC = −2/3 e is (EC)eff = −2/3·10−24 e. It is concluded that the photons, gravitons and dark matters are the first particles created since the big bang. The particles can be created from the decay of the matter universe and the pair production of the particle and anti-particle with decreasing of the gravitation constant (GN(mm)). Also, the weak force, strong force and dark matter force bosons are created from the interactions of the elementary particles with the T fluctuations of the vacuum energy.

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Tempeature Redshift of Photons

10.31219/osf.io/4s6xt ◽

2020 ◽

Author(s):

Xiaoping Hu

Keyword(s):

Dark Matter ◽

Hubble Constant ◽

Big Bang ◽

New Physics ◽

Current Theory ◽

Big Bang Theory ◽

Celestial Bodies ◽

Expansion Force ◽

The Big Bang ◽

The Universe

This article presents a new theory on redshift of light from celestial bodies. Lately it has been found that the Hubble constant calculated from different methods discord so much that calls arise for new physics to explain. Also, in addition to many unsolved puzzles like dark matter and source of expansion force, we shall show in this article that the current theory of redshift implies a few hidden, unreasonale assumptions. By assuming photon has temperature and its thermal energy is fully converted to wave energy, this article shows that photon can have a new redshift called Temperature Redshift, which not only is more significant for remote stars or galaxies, but also better fits the observational data, including those used in Hubble constant calculation. As such, if true, this new theory not only adds to our new understanding of photons, but may totally change our current understanding of the Universe, i.e., the Big Bang theory.

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Charged Dark Matters and Extended Standard Model

10.20944/preprints201806.0225.v2 ◽

2018 ◽

Author(s):

Jae-Kwang Hwang

Keyword(s):

Dark Matter ◽

Three Dimensional ◽

Particle Creation ◽

Big Bang ◽

Space Model ◽

Dark Matters ◽

Effective Charges ◽

The Big Bang ◽

The Universe ◽

Universe Evolution

The properties of the charged dark matters are discussed in terms of the new three-dimensional quantized space model. Because of the graviton evaporations, the very small Coulomb’s constant (k(dd)) of 10 −48 k and large gravitation constant (GN(dd)) of 106 GN for the charged dark matters at the present time are expected. The tentative values of G and k are used for the explanation purpose. Therefore, Fc(mm) > Fg(dd) > Fg(mm) > Fg(dm) > Fc(dd) > Fc(dm) = Fc(lq) = 0 for the proton-like particle. Also, the gravitation constant has been changed with increasing of the time because of the graviton evaporation. In the present work, the B1, B2 and B3 bastons with the condition of k(mm) = k >> k(dd) > k(dm) = 0 are explained as the good candidates of the dark matters. Also, the particle creation, dark matters and dark energy could be deeply associated with the changing gravitation constants (G). It is expected that the changing process of the gravitation constant between the matters from GN(mm) ≈ 1036 GN to GN(mm) = GN happened mostly near the inflation period. Therefore, during most of the universe evolution the gravitation constant could be taken as GN(mm) = GN. And the effective charges and effective rest masses of the particles are defined in terms of the fixed Coulomb’s constant (k) and fixed gravitation constant (GN). Then, the effective charge of the B1 dark matter with EC = −2/3 e is (EC)eff = −2/3·10−24 e. It is concluded that the photons, gravitons and dark matters are the first three particles created since the big bang. The particles can be created from the decay of the matter universe and the pair production of the particle and anti-particle with decreasing of the gravitation constant (GN(mm)).

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