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Cosmology without the Cosmological Principle and without Violating the Copernican Principle: Taub-NUT Universe
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作者 Charles H. McGruder III 《Journal of Modern Physics》 2024年第8期1069-1096,共28页
We develop a theory of cosmology, which is not based on the cosmological principle. We achieve this without violating the Copernican principle. It is well known that the gravitational redshift associated with the Schw... We develop a theory of cosmology, which is not based on the cosmological principle. We achieve this without violating the Copernican principle. It is well known that the gravitational redshift associated with the Schwarzschild solution applied to the distant supernova does not lead to the observed redsift-distance relationship. We show, however, that generalizations of the Schwarzschild metric, the Taub-NUT metrics, do indeed lead to the observed redshift-distance relationship and to the observed time dilation. These universes are not expanding rather the observed cosmological redshift is due to the gravitational redshift associated with these solutions. Time dilation in these stationary universes has the same dependency on redshift that generally has been seen as proof that space is expanding. Our theory resolves the Hubble tension. 展开更多
关键词 cosmology General Relativity
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Cosmological Constraints on Neutrino Masses in Light of JWST Red and Massive Candidate Galaxies
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作者 Jian-Qi Liu Zhi-Qi Huang Yan Su 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期7-12,共6页
The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~10.In the scenari... The overabundance of the red and massive candidate galaxies observed by the James Webb Space Telescope(JWST)implies efficient structure formation or large star formation efficiency at high redshift z~10.In the scenario of a low or moderate star formation efficiency,because massive neutrinos tend to suppress the growth of structure of the universe,the JWST observation tightens the upper bound of the neutrino masses.Assuming A cold dark matter cosmology and a star formation efficiency∈[0.05,0.3](flat prior),we perform joint analyses of Planck+JWST and Planck+BAO+JWST,and obtain improved constraints∑m_(ν)<0.196 eV and ∑m_(ν)+<0.111 eV at 95% confidence level,respectively.Based on the above assumptions,the inverted mass ordering,which implies ∑m_(ν)≥0.1 eV,is excluded by Planck+BAO+JWST at 92.7% confidence level. 展开更多
关键词 (cosmology:)cosmological parameters galaxies:abundances galaxies:formation NEUTRINOS
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Quantifying the Tension between Cosmological Models and JWST Red Candidate Massive Galaxies
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作者 Jun-Chao Wang Zhi-Qi Huang +1 位作者 Lu Huang Jianqi Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期1-6,共6页
We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone.The code is based on the extended Press-Schechter model and i... We develop a Python tool to estimate the tail distribution of the number of dark matter halos beyond a mass threshold and in a given volume in a light-cone.The code is based on the extended Press-Schechter model and is computationally efficient,typically taking a few seconds on a personal laptop for a given set of cosmological parameters.The high efficiency of the code allows a quick estimation of the tension between cosmological models and the red candidate massive galaxies released by the James Webb Space Telescope,as well as scanning the theory space with the Markov Chain Monte Carlo method.As an example application,we use the tool to study the cosmological implication of the candidate galaxies presented in Labbéet al.The standard Λcold dark matter(ΛCDM)model is well consistent with the data if the star formation efficiency can reach~0.3 at high redshift.For a low star formation efficiency ε~0.1,theΛCDM model is disfavored at~2σ-3σconfidence level. 展开更多
关键词 (cosmology:)cosmological parameters Galaxy:abundances Galaxy:formation
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Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae
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作者 Zhenyu Wang Jujia Zhang +1 位作者 Xinzhong Er Jinming Bai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期183-191,共9页
The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients accurately.This telescope system can be crucial in ... The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients accurately.This telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to start.By considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by Mephisto.The best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 days.In this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.Given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia. 展开更多
关键词 (stars:)supernovae:general (cosmology:)cosmological parameters telescopes
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Classical Cosmology II. The Einstein Ring
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作者 Lorenzo Zaninetti 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期574-598,共25页
The Einstein ring is usually explained in the framework of the gravitational lens. Conversely here we apply the framework of the expansion of a superbubble (SB) in order to explain the spherical appearance of the ring... The Einstein ring is usually explained in the framework of the gravitational lens. Conversely here we apply the framework of the expansion of a superbubble (SB) in order to explain the spherical appearance of the ring. Two classical equations of motion for SBs are derived in the presence of a linear and a trigonometric decrease for density. A relativistic equation of motion with an inverse square dependence for the density is derived. The angular distance, adopting the minimax approximation, is derived for three relativistic cosmologies: the standard, the flat and the wCDM. We derive the relation between redshift and Euclidean distance, which allows fixing the radius of the Einstein ring. The details of the ring are explained by a simple version of the theory of images. 展开更多
关键词 cosmology Observational cosmology Gravitational Lenses Luminous Arcs
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The Extremal Universe Exact Solution from Einstein’s Field Equation Gives the Cosmological Constant Directly
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作者 Espen Gaarder Haug 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期386-397,共12页
Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditi... Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditions. Multiple solutions have been utilized to predict cosmic scales, and among them, the Friedmann-Lemaître-Robertson-Walker solution that is the back-bone of the development into today standard model of modern cosmology: The Λ-CDM model. However, this is naturally not the only solution to Einstein’s field equation. We will investigate the extremal solutions of the Reissner-Nordström, Kerr, and Kerr-Newman metrics. Interestingly, in their extremal cases, these solutions yield identical predictions for horizons and escape velocity. These solutions can be employed to formulate a new cosmological model that resembles the Friedmann equation. However, a significant distinction arises in the extremal universe solution, which does not necessitate the ad hoc insertion of the cosmological constant;instead, it emerges naturally from the derivation itself. To the best of our knowledge, all other solutions relying on the cosmological constant do so by initially ad hoc inserting it into Einstein’s field equation. This clarification unveils the true nature of the cosmological constant, suggesting that it serves as a correction factor for strong gravitational fields, accurately predicting real-world cosmological phenomena only within the extremal solutions of the discussed metrics, all derived strictly from Einstein’s field equation. 展开更多
关键词 General Relativity Theory cosmological Constant Extremal Solution Reissner-Nordström KERR Kerr-Newman
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Legendre-Jacobi’s Elliptic Integrals Shed Light on the Luminosity Distance in Cosmology
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作者 Alessandro Trinchera 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期930-957,共28页
This article concerns the integral related to the transverse comoving distance and, in turn, to the luminosity distance both in the standard non-flat and flat cosmology. The purpose is to determine a straightforward m... This article concerns the integral related to the transverse comoving distance and, in turn, to the luminosity distance both in the standard non-flat and flat cosmology. The purpose is to determine a straightforward mathematical formulation for the luminosity distance as function of the transverse comoving distance for all cosmology cases with a non-zero cosmological constant by adopting a different mindset. The applied method deals with incomplete elliptical integrals of the first kind associated with the polynomial roots admitted in the comoving distance integral according to the scientific literature. The outcome shows that the luminosity distance can be obtained by the combination of an analytical solution followed by a numerical integration in order to account for the redshift. This solution is solely compared to the current Gaussian quadrature method used as basic recognized algorithm in standard cosmology. 展开更多
关键词 cosmology Distance Luminosity Transverse Comoving Distance Incomplete Elliptic Integrals
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Hubble Tension Explanation from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期106-125,共20页
In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of t... In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of the evolution of space-time as well as an equation of state that retains all the infinitesimal terms. We find an explanation of the Hubble tension H<sub>0</sub>. Indeed, we have seen that this constant depends on the transceiver pair which can vary from the lowest observable value, from photons of the CMB (theoretical [km/s/Mpc]) to increasingly higher values depending on the earlier origin of the formation of the observed galaxy or cluster (ETG ~0.3 [Gy], ~74 [km/s/Mpc]). We have produced a theoretical table of the values of the constant according to the possible pairs of transmitter/receiver in the case where these galaxies follow the Hubble flow without large disturbance. The calculated theoretical values of the constant are in the order of magnitude of all values mentioned in past studies. Subsequently, we applied the models to 9 galaxies and COMA cluster and found that the models predict acceptable values of their distances and Hubble constant since these galaxies mainly follow the Hubble flow rather than the effects of a galaxy cluster or a group of clusters. In conclusion, we affirm that this Hubble tension does not really exist and it is rather the understanding of the meaning of this constant that is questioned. 展开更多
关键词 Model of the Universe cosmological Constant Hubble Constant Hubble’s Tension Hubble-Lemaître Law Hubble’s Flow
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Classical Cosmology I. Anomalous Redshift for Galaxies in NED-D
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作者 Lorenzo Zaninetti 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期8-26,共19页
Three mechanisms for an alternative to the Doppler effect as an explanation for the redshift are reviewed. A fourth mechanism is the attenuation of the light as given by the Beer-Lambert law. The average value of the ... Three mechanisms for an alternative to the Doppler effect as an explanation for the redshift are reviewed. A fourth mechanism is the attenuation of the light as given by the Beer-Lambert law. The average value of the Hubble constant is therefore derived by processing the galaxies of the NED-D catalog in which the distances are independent of the redshift. The observed anisotropy of the Hubble constant is reproduced by adopting a rim model, a chord model, and both 2D and 3D Voronoi diagrams. 展开更多
关键词 Galaxy Groups Clusters SUPERCLUSTERS Large Scale Structure of the Universe cosmology
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 Scale-Symmetric Theory Tension cosmology Coupling Constants Parameters σ8 and S8 Largest Cosmic Structures Dark Energy Supernova Explosion Cyclic Universe
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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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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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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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Time Dilation Cosmology 2
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第4期448-461,共14页
This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conu... This paper is a further elaboration of the author’s Time Dilation Cosmology (TDC) holographic model that ties gravitation and celestial mechanics and kinematics directly to time dilation, resolving all the major conundrums in astrophysics, and ties astrophysics directly to quantum physics. It begins with a brief summary of the TDC model and contains the new derivation for the time dilation version of the formula for summing relativistic velocities, Einstein’s gravitational constant and the time dilation versions for the Lorentz factor and the Euclidean norm of the 3d velocity vector, the two of which can then be used in the Four-velocity formula. It is demonstrated how orbital curvature is manifested as the resultant of two time dilation-manifested velocities. It also explains why an interferometer cannot distinguish free fall from zero gravity and further elaborates on the author’s previous explanations of how spiral galaxies are formed, and contains mathematical proof that Black Holes are actually Magnetospheric Eternally Collapsing Objects (MECOs) that are massless spacetime vortices. 展开更多
关键词 GRAVITATION Time Time Dilation Celestial Mechanics ISM: Kinematics and Dynamics cosmology: Theory Galaxies: Evolution
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Cosmological Model in Four Time and Four Space Dimensions
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作者 Juan Antonio Nieto 《Journal of Applied Mathematics and Physics》 2024年第3期829-840,共12页
We develop a cosmological model in a physical background scenario of four time and four space dimensions ((4+4)-dimensions or (4+4)-universe). We show that in this framework the (1+3)-universe is deeply connected with... We develop a cosmological model in a physical background scenario of four time and four space dimensions ((4+4)-dimensions or (4+4)-universe). We show that in this framework the (1+3)-universe is deeply connected with the (3+1)-universe. We argue that this means that in the (4+4)-universe there exists a duality relation between the (1+3)-universe and the (3+1)-universe. 展开更多
关键词 cosmological Model (4+4)-Dimensions Duality Symmetry
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Cosmological Gravitational Redshift, Spectral Shift and Time in the Taub-NUT Universe
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作者 Charles H. McGruder III 《Journal of Modern Physics》 2024年第9期1448-1459,共12页
We demonstrate that: 1) The Taub-NUT universe is finite. 2) The Taub-NUT universe is much larger than the maximum observable distance according to the standard theory of cosmology. 3) At large distances the spectral s... We demonstrate that: 1) The Taub-NUT universe is finite. 2) The Taub-NUT universe is much larger than the maximum observable distance according to the standard theory of cosmology. 3) At large distances the spectral shift turns into a blueshift. 4) At large distances time dilation turns into time contraction. 展开更多
关键词 cosmology General Relativity
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Non Linear Electrodynamics Contributing to a Minimum Vacuum Energy (“Cosmological Constant”) Allowed in Early Universe Cosmology 被引量:3
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第1期25-32,共8页
This article poses the question of a minimum cosmological constant, i.e. vacuum energy at the start of the cosmological evolution from a near singularity. We pose this comparing formalism as given by Berry (1976) as t... This article poses the question of a minimum cosmological constant, i.e. vacuum energy at the start of the cosmological evolution from a near singularity. We pose this comparing formalism as given by Berry (1976) as to a small time length, and compare that in its entirety to compare this value given by Berry (1976) with a minimum time length at the start of cosmological space-time evolution. Using the methodology of Zeldovich (1972) as to a problem with electron-positron pair production we also propose another upper bound to the problem of minimum time length which may be accessible to experimental inquiry. This then makes the problem of minimum time length a way of specifying a magnetic field dependence of the cosmological constant, which has major implications to answering if quintessence, i.e. a changing cosmological vacuum energy, or a constant for the “cosmological constant” problem. Our answer is an initial value for the cosmological vacuum energy 10<sup>10</sup> - 10<sup>20</sup> times greater than today which suggests either Quintessence, or if still a constant, a much better value for this parameter than what is suggested by traditional field theory methods. In closing we review how our construct supports work done by Corda, as to early universe models and what the implications are, as to the choices we have made. 展开更多
关键词 cosmological Vacuum Energy Energy Density Initial Time Step
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An Exact Scalar Field Inflationary Cosmological Model Which Solves Cosmological Constant Problem, Dark Matter Problem and Other Problems of Inflationary Cosmology
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作者 Debasis Biswas 《Journal of Modern Physics》 2013年第8期172-182,共11页
An exact scalar field cosmological model is constructed from the exact solution of the field equations. The solutions are exact and no approximation like slow roll is used. The model gives inflation, solves horizon an... An exact scalar field cosmological model is constructed from the exact solution of the field equations. The solutions are exact and no approximation like slow roll is used. The model gives inflation, solves horizon and flatness problems. The model also gives a satisfactory estimate of present vacuum energy density as well as vacuum energy density at Planck epoch and solves cosmological constant problem of 120 orders of magnitude discrepancy of vacuum energy density. Further, this model predicts existence of dark matter/energy and gives an extremely accurate estimate of present energy density of dark matter and energy. Along with explanations of graceful exit, radiation era, matter domination, this model also indicates the reason for present accelerated state of the universe. In this work a method is shown following which one can construct an infinite number of exact scalar field inflationary cosmological models. 展开更多
关键词 INFLATIONARY cosmology cosmological Constant DARK MATTER
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The Formula to Calculate the Red Shift-Distance Relation of Ia Supernova in Cosmology Has Essential Mistakes —The Calculation of Cosmological Red Shift Should Use the Doppler Formula Directly
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作者 Xiaochun Mei Ping Yu 《International Journal of Astronomy and Astrophysics》 2012年第3期183-193,共11页
There are three main mechanisms to cause the red shift of spectrum in physics. The first is gravity which is related to mass. The second is the Compton scattering which is related to the energy transformation of photo... There are three main mechanisms to cause the red shift of spectrum in physics. The first is gravity which is related to mass. The second is the Compton scattering which is related to the energy transformation of photon. The third is the Doppler’s effect which is related to velocity. The basic formula used to calculate the relation of red shift and distance of Ia supernova in cosmology is which is related to the scalar factor of the R-W metric. It is completely different from the Doppler formula of red shift which is related to velocity factor . This kind of inconsistency is not allowed in physics. Because of , when became larger and larger with time increase, z became smaller and smaller, means that space expansion leads to red shift becoming smaller. At present time, we have and , means that there is no red shift for the light emitted from distance celestial bodies at present. The results obviously violate the Hubble law! It is proved strictly in mathematics that the formula is untenable unless constant and . The further study reveals that the essential reason of the mistake is that the R-W metric violates the principle of light’s speed invariable. The time delay caused by relativity velocity between light’s source and observer is neglected. Besides, there exists the problem of time misalignment between theoretical calculation and practical observations in the original documents of Ia supernova projects. So the formula used to calculate the relation between red shift and distance of Ia supernova is wrong and the deduced conclusion about dark energy and the accelerating expansion of the universe are incredible. It is proved in this paper that based on the Doppler’s formula and the method of numerical calculation, the relation of red shift and distance of Ia supernova can be explained well. The hypotheses of dark energy and the accelerating expansion of the universe are completely unnecessary in cosmology. 展开更多
关键词 cosmology DOPPLER FORMULA HUBBLE Law SUPERNOVA Dark Energy R-W Metric
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Cosmology of a Chaplygin Gas Model Under f(T)Gravity and Evolution of Primordial Perturbations
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作者 Sanjeeda Sultana Surajit Chattopadhyay 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期187-198,共12页
This paper reports a detailed study of generalized Chaplygin gas(GCG)with power law form of scale factor and truncated form of the scale factor using binomial expansion in both interacting and non-interacting scenario... This paper reports a detailed study of generalized Chaplygin gas(GCG)with power law form of scale factor and truncated form of the scale factor using binomial expansion in both interacting and non-interacting scenarios along with its cosmological consequences,studied in terms of equation of state(EoS)parameter.In the non-interacting scenario,the EoS parameter behaves as quintessence in both forms of the scale factor.In the interacting scenario,the EoS parameter behaves as phantom and for the truncated form of the scale factor,it violates the constraints of the positive parameterα.The cosmological implementation of GCG interacting with pressureless dark matter is investigated in the framework of f(T)modified gravity,where T is the torsion scalar in teleparallelism.The interaction term is directly proportional to the GCG density with positive coupling constant.In f(T)gravity,the EoS is behaving like phantom.The stability of the reconstructed model is investigated and it is found to be stable against small gravitational perturbations,i.e.,the squared speed of sound is non-negative and an increasing function of cosmic time t.We have observed that our reconstructed f(T)model satisfies one of the sufficient conditions of a realistic reconstructed model and it is consistent with the CMB constraints and primordial nucleosynthesis.Cosmology of primordial perturbations has also been analyzed and the self-interacting potential has been found to be an increasing function of cosmic time t. 展开更多
关键词 (cosmology:)dark energy cosmology:theory (cosmology:)cosmological parameters
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