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Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期167-173,共7页
This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper su... This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper summarizes the current state of quantum cosmology with respect to the Flat Space Cosmology (FSC) model. Although the FSC quantum cosmology formulae were published in 2018, they are only rearrangements and substitutions of the other assumptions into the original FSC Hubble temperature formula. In a real sense, this temperature formula was the first quantum cosmology formula developed since Hawking’s black hole temperature formula. A recent development in the last month proves that the FSC Hubble temperature formula can be derived from the Stephan-Boltzmann law. Thus, this Hubble temperature formula effectively unites some quantum developments with the general relativity model inherent in FSC. More progress towards unification in the near-future is expected. 展开更多
关键词 quantum cosmology Hubble Constant Planck Scale Upsilon Constant Flat Space cosmology Black Holes CMB Temperature ΛCDM cosmology quantum Gravity Unification
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Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology
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作者 Sara Benchikh Noureddine Mebarki Dalel Aberkane 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期144-148,共5页
Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop q... Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data. 展开更多
关键词 of on in Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop quantum cosmology is that for been FRW
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Viscous Modified Chaplygin Gas in Classical and Loop Quantum Cosmology
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作者 D. Aberkane N. Mebarki S. Benchikh 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期139-143,共5页
We investigate the cosmological model of viscous modified Chaplygin gas (VMCG) in classical and loop quantum cosmology (LQC). Firstly, we constrain its equation of state parameters in the framework of standard cos... We investigate the cosmological model of viscous modified Chaplygin gas (VMCG) in classical and loop quantum cosmology (LQC). Firstly, we constrain its equation of state parameters in the framework of standard cosmology from Union 2.1 SNe Ia data. Then, we probe the dynamical stability of this model in a universe filled with VMCG and baryonic fluid in LQC background. It is found that the model is very suitable with (χ2/d.o.f = 0.974) and gives a good prediction of the current values of the deceleration parameter q0 =∈ (-0.60, -0.57) and the effective state parameter ωeff∈ (-0.76, -0.74) that is consistent with the recent observational data. The model can also predict the time crossing when (ρDE ≈ Pmatter) at z = 0.75 and can solve the coincidence problem. In LQC background, the Big Bang singularity found in classical cosmology ceases to exist and is replaced by a bounce when the Hubble parameter vanishes at ρtot≈ρc. 展开更多
关键词 Viscous Modified Chaplygin Gas in Classical and Loop quantum cosmology
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How the Flat Space Cosmology Model Correlates the Recombination CMB Temperature of 3000 K with a Redshift of 1100
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作者 Eugene Terry Tatum U. V. S. Seshavatharam 《Journal of Modern Physics》 2024年第2期174-178,共5页
This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the... This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is given in support of the recent publication that the Tatum and Seshavatharam Hubble temperature formulae can be derived using the Stephan-Boltzmann dispersion law. Thus, as explained herein, the era of high precision Planck scale quantum cosmology has arrived. 展开更多
关键词 Hubble Constant Cosmic Microwave Background quantum cosmology Stephan-Boltzmann Upsilon Coupling Constant Flat Space cosmology ΛCDM cosmology
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Energy conditions in the new model of loop quantum cosmology
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作者 龙高平 刘云龙 张向东 《Chinese Physics C》 SCIE CAS CSCD 2021年第11期143-150,共8页
Recently,a de-Sitter epoch has been found in the new model of loop quantum cosmology,which is governed by the scalar constraint with both Euclidean and Lorentz terms.The singularity free bounce in the new LQC model an... Recently,a de-Sitter epoch has been found in the new model of loop quantum cosmology,which is governed by the scalar constraint with both Euclidean and Lorentz terms.The singularity free bounce in the new LQC model and the emergent cosmology constant strongly suggest that the effective stress-energy tensor induced by quantum corrections must violate the standard energy conditions.In this study,we perform an explicit calculation to analyze the behaviors of specific representative energy conditions,i.e.,average null,strong,and dominant energy conditions.We reveal that the average null energy condition is violated at all times,while the dominant energy condition is violated only at a period around the bounce point.The strong energy condition is violated not only at a period around the bounce point but also in the whole period from the bounce point to the classical phase corresponding to the de Sitter period.Our results will shed some light on the construction of a wormhole and time machine,which usually require exotic matter to violate energy conditions. 展开更多
关键词 energy condition loop quantum cosmology quantum gravity
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Dynamics of k-essence in loop quantum cosmology
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作者 石家丽 吴健聘 《Chinese Physics C》 SCIE CAS CSCD 2021年第4期451-461,共11页
In this paper,we study the dynamics of k-essence in loop quantum cosmology(LQC).The study indicates that the loop quantum gravity(LQG)effect plays a key role only in the early epoch of the universe and is diluted in t... In this paper,we study the dynamics of k-essence in loop quantum cosmology(LQC).The study indicates that the loop quantum gravity(LQG)effect plays a key role only in the early epoch of the universe and is diluted in the later stages.The fixed points in LQC are basically consistent with those in standard Friedmann-Robertson-Walker(FRW)cosmology.For most of the attractor solutions,the stability conditions in L Q C are in agreement with those for the standard FRW universe.For some special fixed points,however,tighter constraints are imposed thanks to the LQG effect. 展开更多
关键词 K-ESSENCE loop quantum cosmology dynamics of dark energy
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A Solution to the Cosmological Constant Problem Using the Holographic Principle (A Brief Note)
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期159-166,共8页
This paper integrates a quantum conception of the Planck epoch early universe with FSC model formulae and the holographic principle, to offer a reasonable explanation and solution of the cosmological constant problem.... This paper integrates a quantum conception of the Planck epoch early universe with FSC model formulae and the holographic principle, to offer a reasonable explanation and solution of the cosmological constant problem. Such a solution does not appear to be achievable in cosmological models which do not integrate black hole formulae with quantum formulae such as the Stephan-Boltzmann law. As demonstrated herein, assuming a constant value of Lambda over the great span of cosmic time appears to have been a mistake. It appears that Einstein’s assumption of a constant, in terms of vacuum energy density, was not only a mistake for a statically-balanced universe, but also a mistake for a dynamically-expanding universe. 展开更多
关键词 quantum cosmology Planck Scale Cosmological Constant Black Holes Holographic Principle Flat Space cosmology AdS-CFT ER = EPR cosmology Model
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On the Cosmic Evolution of the Quantum Vacuum Using Two Variable G Models and Winterberg’s Thesis
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1134-1160,共27页
We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckion... We work within a Winterberg framework where space, i.e., the vacuum, consists of a two component superfluid/super-solid made up of a vast assembly (sea) of positive and negative mass Planck particles, called planckions. These material particles interact indirectly, and have very strong restoring forces keeping them a finite distance apart from each other within their respective species. Because of their mass compensating effect, the vacuum appears massless, charge-less, without pressure, net energy density or entropy. In addition, we consider two varying G models, where G, is Newton’s constant, and G<sup>-1</sup>, increases with an increase in cosmological time. We argue that there are at least two competing models for the quantum vacuum within such a framework. The first follows a strict extension of Winterberg’s model. This leads to nonsensible results, if G increases, going back in cosmological time, as the length scale inherent in such a model will not scale properly. The second model introduces a different length scale, which does scale properly, but keeps the mass of the Planck particle as, ± the Planck mass. Moreover we establish a connection between ordinary matter, dark matter, and dark energy, where all three mass densities within the Friedman equation must be interpreted as residual vacuum energies, which only surface, once aggregate matter has formed, at relatively low CMB temperatures. The symmetry of the vacuum will be shown to be broken, because of the different scaling laws, beginning with the formation of elementary particles. Much like waves on an ocean where positive and negative planckion mass densities effectively cancel each other out and form a zero vacuum energy density/zero vacuum pressure surface, these positive mass densities are very small perturbations (anomalies) about the mean. This greatly alleviates, i.e., minimizes the cosmological constant problem, a long standing problem associated with the vacuum. 展开更多
关键词 Winterberg Model Planck Particles Positive and Negative Mass Planck Particles Planckions quantum Vacuum Space as a Superfluid/Supersolid Extended Models for Space Cosmological Constant Higgs Field as a Composite Particle Higgs Boson Inherent Length Scale for the Vacuum Dark Energy Cosmological Scaling Behavior for the quantum Vacuum Variable G Models Extended Gravity Newton’s Constant as an Order Parameter High Energy Behavior for the Vacuum
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