scholarly journals The evolution of the universe in asymmetric cosmic time

2021 ◽  
Vol 4 (3) ◽  
Keyword(s):  
Energy Density ◽  
Nuclear Force ◽  
Vacuum Energy ◽  
Cosmic Time ◽  
Big Bang ◽  
Vacuum Energy Density ◽  
De Sitter ◽  
Planck Time ◽  
The Big Bang ◽  
The Universe

The Cosmic Time Hypothesis (CTH) presented in this paper is a purely axiomatic theory. In contrast to today's standard model of cosmology, the ɅCDM model, it does not contain empirical parameters such as the cosmological constant Ʌ, nor does it contain sub-theories such as the inflation theory. The CTH was developed solely on the basis of the general theory of relativity (GRT), aiming for the greatest possible simplicity. The simplest cosmological model permitted by ART is the Einstein-de Sitter model. It is the basis for solving some of the fundamental problems of cosmology that concern us today. First of all, the most important results of the CTH: It solves one of the biggest problems of cosmology the problem of the cosmological constant (Ʌ)-by removing the relation between and the vacuum energy density ɛv (Λ=0, ɛv > 0). According to the CTH, the vacuum energy density ɛv is not negative and constant, as previously assumed, but positive and time-dependent (ɛv ̴ t -2). ɛv is part of the total energy density (Ɛ) of the universe and is contained in the energy-momentum tensor of Einstein's field equations. Cosmology is thus freed from unnecessary ballast, i.e. a free parameter (= natural constant) is omitted (Ʌ = 0). Conclusion: There is no "dark energy"! According to the CTH, the numerical value of the vacuum energy density v is smaller by a factor of ≈10-122 than the value calculated from quantum field theory and is thus consistent with observation. The measurement data obtained from observations of SNla supernovae, which suggest a currently accelerated expansion of the universe, result - if interpreted from the point of view of the CTH - in a decelerated expansion, as required by the Einstein-de Sitter universe. Dark matter could also possibly not exist, because the KZH demands that the "gravitational constant" is time-dependent and becomes larger the further the observed objects are spatially and thus also temporally distant from us. Gravitationally bound local systems, e.g. Earth - Moon or Sun - Earth, expand according to the same law as the universe. This explains why Hubble's law also applies within very small groups of galaxies, as observations show. The CTH requires that the strongest force (strong nuclear force) and the weakest (gravitational force) at Planck time (tp ≈10-43 seconds after the "big bang") when all forces of nature are supposed to have been united in a single super force, were of equal magnitude and had the same range. According to the KZH, the product of the strength and range of the gravitational force is constant, i.e. independent of time, and is identical to the product of the strength and range of the strong nuclear force. At Planck time, the universe had the size of an elementary particle (Rp = rE ≈10-15 m). This value also corresponds to the range of the strong nuclear force (Yukawa radius) and the Planck length at Planck time. The CTH provides a possible explanation for Mach's first and second principles. It solves some old problems of the big bang theory in a simple and natural way. The problem of the horizon, flatness, galaxy formation and the age of the world. The inflation theory thus becomes superfluous. • The CTH provides the theoretical basis for the theory of Earth expansion • In Cosmic Time, there was no Big Bang. The universe is infinitely old. • Unlike other cosmological models, the CTH does not require defined "initial conditions" because there was no beginning. • The CTH explains why the cosmic expansion is permanently in an unstable state of equilibrium, which is necessary for a long-term flat (Euclidean), evolutionarily developing universe.

scholarly journals Decaying vacuum and evolution from early inflation to late acceleration

2021 ◽  
pp. 2150160
Author(s):  
N. Sarath ◽  
Titus K. Mathew
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Friedmann Equation ◽  
Time Dependent ◽  
Vacuum Energy Density ◽  
De Sitter ◽  
Unified Framework ◽  
Number Formula ◽  
Hubble Radius ◽  
The Universe

Decaying vacuum models are a class of models that incorporate a time-dependent vacuum energy density that can explain the entire evolution of the universe in a unified framework. A general solution to the Friedmann equation is obtained by considering vacuum energy density as a function of the Hubble parameter. We have obtained the asymptotic solution by choosing the equation of state for matter, [Formula: see text] and radiation, [Formula: see text]. Finite boundaries in the early and late de Sitter epoch are defined by considering the evolution of primordial perturbation wavelength. An epoch invariant number [Formula: see text] determines the number of primordial perturbation modes that cross the Hubble radius during each epoch.

scholarly journals An Alternative Approach to Estimate the Vacuum Energy Density of Free Space

2017 ◽  
Author(s):  
Vernon Cooray ◽  
Gerald Cooray ◽  
Farhad Rachidi
Keyword(s):  
Energy Density ◽  
Particle Physics ◽  
Vacuum Energy ◽  
Empty Space ◽  
Negative Energy ◽  
Accelerated Expansion ◽  
Vacuum Energy Density ◽  
Net Energy ◽  
Planck Time ◽  
The Universe

According to the current understanding, the recently observed   accelerated expansion of the universe is caused by the dark or the vacuum energy. Attempts to calculate the magnitude of this energy using the standard model of particle physics led to values which are 59 – 120 orders of magnitude larger than the experimentally estimated one. Even though the expanding space has positive internal energy, in a flat universe it is completely balanced by the negative energy of gravitational field making the net energy equal to zero. However, the current physical theories may breakdown for times less than or on the order of Planck time and one cannot assume that the above assertion concerning the balance of two energies is valid also in this time scale. In this note it is assumed that this balance of the two energies during the creation of new space as the universe expands takes place only for times larger than the Planck time. If this assumption is correct, the net energy of the newly created space remains positive for times on the order of Planck time and the positive vacuum energy has to be burrowed from empty space before it is being balanced by gravity. This can happen only within the restrictions of the time-energy uncertainty principle. In this note it is shown that such considerations lead to a vacuum energy density of about 0.3 Nanojoules per cubic meter which has to be compared with the measured value of 0.6 Nanojoules per cubic meter.

scholarly journals FROM INFLATION TO DARK ENERGY THROUGH A DYNAMICAL Λ: AN ATTEMPT AT ALLEVIATING FUNDAMENTAL COSMIC PUZZLES

2013 ◽  
Vol 22 (12) ◽  
pp. 1342008 ◽  
Author(s):  
SPYROS BASILAKOS ◽  
JOSÉ ADEMIR SALES LIMA ◽  
JOAN SOLÀ
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Big Bang ◽  
Vacuum Energy Density ◽  
Late Time ◽  
De Sitter ◽  
New Class ◽  
Sitter Spacetime ◽  
Inflationary Phase ◽  
De Sitter Vacuum

After decades of successful hot big-bang paradigm, cosmology still lacks a framework in which the early inflationary phase of the universe smoothly matches the radiation epoch and evolves to the present "quasi" de Sitter spacetime. No less intriguing is that the current value of the effective vacuum energy density is vastly smaller than the value that triggered inflation. In this paper, we propose a new class of cosmologies capable of overcoming, or highly alleviating, some of these acute cosmic puzzles. Powered by a decaying vacuum energy density, the spacetime emerges from a pure nonsingular de Sitter vacuum stage, "gracefully" exits from inflation to a radiation phase followed by dark matter and vacuum regimes, and, finally, evolves to a late-time de Sitter phase.

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.

THE DISCOVERY OF THE EXPANDING UNIVERSE AND 80 YEARS OF BIG BANG

2011 ◽  
Vol 20 (supp01) ◽  
pp. 87-103 ◽  
Author(s):  
HARRY NUSSBAUMER
Keyword(s):  
Big Bang ◽  
Rapid Expansion ◽  
Condensed State ◽  
De Sitter ◽  
Static Universe ◽  
Linear Distance ◽  
Velocity Relationship ◽  
Modern Cosmology ◽  
The Big Bang ◽  
The Universe

Modern cosmology began in 1917 when Einstein published his model of a static Universe built on general relativity. A few months later de Sitter came forward with a competing, but also static model which contained no matter but had the intriguing quality that the spectrum of a test particle appeared redshifted to a distant observer. It was thought that de Sitter's model might explain the redshifted spectra observed by Slipher in spiral nebulae. However, in 1927 Lemaître showed that de Sitter's model violated the principle of homogeneity. He then formulated a dynamical cosmological model and combined it with the available observations, showing that our Universe is expanding. He theoretically derived the linear distance–velocity relationship which today is called the "Hubble-relation." Hubble confirmed the relation in 1929 on purely observational grounds. 80 years ago, in 1931 in a letter to Nature, Lemaître suggested that the Universe had a definite beginning in a rapid expansion out of a highly condensed state: the primeval atom. This event became later known as the Big Bang.

BIG BANG NUCLEOSYNTHESIS WITH A CONSTANT VACUUM ENERGY MOTIVATED BY CYCLIC COSMOLOGY

2011 ◽  
Vol 26 (02) ◽  
pp. 331-339
Author(s):  
S. KALITA ◽  
H. L. DUORAH ◽  
K. DUORAH
Keyword(s):  
Energy Density ◽  
Extra Dimension ◽  
Vacuum Energy ◽  
Mass Difference ◽  
Big Bang ◽  
Upper Bounds ◽  
Rapid Expansion ◽  
Vacuum Energy Density ◽  
Temperature Relation ◽  
Freeze Out

Abundances of primordial deuterium, [Formula: see text] and helium, Yp, are examined by modifying the early universe expansion rate and hence the time–temperature relation, including a constant vacuum energy motivated by the cyclic scenario of brane cosmology. Enhancement of abundances with respect to standard BBN prediction is found. Rapid expansion leads to early freeze-out of weak interaction and hence to an enhanced neutron fraction at elevated freeze-out temperature, which in turn results in more helium. Nucleosynthesis at a much lower temperature (due to rapid expansion) faces a larger Coulomb barrier and leaves more deuterium behind, which is also implied by a lower baryon-to-photon ratio (η) as we increase the vacuum energy density. The change in the helium fraction agrees within orders of magnitudes with that found by the effect of more neutrino flavors on Yp. Elevation of the neutron fraction at freeze-out is revealed by decrease in the neutron–proton mass difference (Q) from 1.293 MeV to 1.279 MeV, which is consistent with the study of the influence of extra dimension size on BBN. The lowest Q value corresponds to the highest vacuum energy and also to the largest size of the extra dimension. The upper limit on vacuum energy density is found by estimating the contribution from nonbaryonic dark matter by using X-ray emission from galaxy clusters and taking a flat spatial geometry, which is found to be the cosmological constant (Λ) observed today, so that the abundances do not run beyond the observational upper bounds. The allowed range of ΩΛ, 0.786 ≤ Ω Λ ≤ 0.844, makes Yp and [Formula: see text] lie within the observational upper bounds, which yields a Big Bang equivalence of the Λ universe. This is expected to further motivate the cyclic scenario, which incorporates a small and constant vacuum energy density tied to spacetime.

scholarly journals The Asymmetric Cosmic Time – The Key to a New Cosmological Model

2020 ◽  
Vol 2 (1) ◽  
pp. 97-111
Author(s):  
Horst Fritsch ◽  
Eberhard Schluecker
Keyword(s):  
Cosmological Model ◽  
Initial Conditions ◽  
Logical Consequence ◽  
Cosmic Time ◽  
Big Bang ◽  
Relativity Theory ◽  
Accelerated Expansion ◽  
Theory Of Relativity ◽  
De Sitter ◽  
The Universe

The asymmetric cosmic time is a logical consequence of the General Theory of Relativity (GR), if one demands that it should apply to the entire cosmos. From the simplest cosmological model that is consistent with the ART (Einstein-de Sitter model) thus follows the < Cosmic Time Hypothesis > (CTH), which offers solutions for many unsolved problems of cosmology that the current standard model of cosmology (ɅCDM model) cannot explain. According to the CTH, space, time and matter form a unit and develop evolutionarily according to identical, time-dependent laws. According to the CTH time has neither beginning nor end. The "big bang" disappears into the infinite past, which is why the universe manages without inflation. The accelerated expansion of the universe is also unlikely to occur if the SN-Ia measurement results are interpreted using the CTH. The cosmological constant Ʌ can then be omitted (Ʌ=0) and consequently no "dark energy" is needed. In addition, the CTH also provides interesting results on the topics: Initial conditions for hypotheses, stability of the expanding, flat universe (Ω=1), cosmic energy balance (is there negative energy ?), theory of earth expansion, unification of natural forces, Mach's principle. Should the CTH receive broad experimental confirmation, the GR could be extended to the "Universal Relativity Theory" (UR).

scholarly journals Charged Dark Matters and Extended Standard Model

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&rsquo;s constant (k(dd)) of 10 &minus;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) &gt; Fg(dd) &gt; Fg(mm) &gt; Fg(dm) &gt; Fc(dd) &gt; 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 &gt;&gt; k(dd) &gt; 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) &asymp; 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&rsquo;s constant (k) and fixed gravitation constant (GN). Then, the effective charge of the B1 dark matter with EC = &minus;2/3 e is (EC)eff = &minus;2/3&middot;10&minus;24 e.&nbsp;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.

scholarly journals Dark Energy is a Phenomenal Effect of the Expanding Universe-Possibility for Experimental Verification.

2020 ◽  
Author(s):  
Siva Prasad Kodukula
Keyword(s):  
Dark Energy ◽  
Experimental Verification ◽  
Quantum Physics ◽  
Vacuum Energy ◽  
Background Radiation ◽  
Big Bang ◽  
Space Time ◽  
Vacuum Energy Density ◽  
The Universe ◽  
Time Density

Abstract Vacuum energy density has been defined and mass formation from ‘space-time’ has been viewed in a different perspective. This explanation for vacuum energy is based on ‘space-time’ and conversion of space in to time keeping ‘space-time density’ as constant. Equations for ‘space-time’ and mutual conversion of space and time have been derived. As a result, new concept of mass creation has been explained. By postulating that space time density of universe is constant, low and high values of cosmological constants has been shown as the exchange of energy between space, time and energy. The concept has been used to explain dark energy concept of the universe. It concluded a result that velocity of light is changing with the apparent expansion of the universe. The derived equation is possible for experimental verification. Obviously it is a contradiction to Big bang model. So the derived equation with the help of quantum concepts explained the 2.7o K cosmic micro wave background radiation. Finally it proposed a relation between diameter of hydrogen atom and Hubble’s constant with another postulate that gives importance to the existence of positive and negative charges below atomic level that describe the basic facts of quantum physics.

IMPORTANT REMARKS ON (ANTI) de SITTER SPACES AND THE COSMOLOGICAL CONSTANT

2006 ◽  
Vol 21 (35) ◽  
pp. 2685-2701 ◽  
Author(s):  
CARLOS CASTRO
Keyword(s):  
Energy Density ◽  
Cosmological Constant ◽  
Vacuum Energy ◽  
Radial Function ◽  
Vacuum Energy Density ◽  
De Sitter ◽  
Cosmological Constant Problem ◽  
Natural Explanation ◽  
Observable Universe ◽  
Weyl Geometry

A class of proper and novel generalizations of the (anti) de Sitter solutions (parametrized by a family of radial functions R(r)) are presented that could provide a very plausible resolution of the cosmological constant problem along with a natural explanation of the ultraviolet/infrared (uv/ir) entanglement required to solve this problem. A nonvanishing value of the vacuum energy density of the order of [Formula: see text] is derived in agreement with the experimental observations. The presence of the radial function R(r) is instrumental to understand why the cosmological constant is not zero and why it is so tiny. The correct lower estimate of the mass of the observable universe related to the Dirac–Eddington's large number N = 1080 is also obtained. Finally we present our most recent findings of how Weyl Geometry via a Brans–Dicke scalar field solves the riddle of dark energy in addition to providing another derivation of the vacuum energy density.

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