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Cosmic Acceleration and the Hubble Tension from Baryon Acoustic Oscillation Data
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作者 Xuchen Lu Shengqing Gao Yungui Gong 《Chinese Physics Letters》 2026年第1期327-332,共6页
We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parame... We investigate the null tests of cosmic accelerated expansion by using the baryon acoustic oscillation(BAO)data measured by the dark energy spectroscopic instrument(DESI)and reconstruct the dimensionless Hubble parameter E(z)from the DESI BAO Alcock-Paczynski(AP)data using Gaussian process to perform the null test.We find strong evidence of accelerated expansion from the DESI BAO AP data.By reconstructing the deceleration parameter q(z) from the DESI BAO AP data,we find that accelerated expansion persisted until z■0.7 with a 99.7%confidence level.Additionally,to provide insights into the Hubble tension problem,we propose combining the reconstructed E(z) with D_(H)/r_(d) data to derive a model-independent result r_(d)h=99.8±3.1 Mpc.This result is consistent with measurements from cosmic microwave background(CMB)anisotropies using the ΛCDM model.We also propose a model-independent method for reconstructing the comoving angular diameter distance D_(M)(z) from the distance modulus μ,using SNe Ia data and combining this result with DESI BAO data of D_(M)/r_(d) to constrain the value of r_(d).We find that the value of r_(d),derived from this model-independent method,is smaller than that obtained from CMB measurements,with a significant discrepancy of at least 4.17σ.All the conclusions drawn in this paper are independent of cosmological models and gravitational theories. 展开更多
关键词 baryon acoustic oscillation bao data cosmic accelerated expansion dimensionless hubble parameter reconstructing deceleration parameter null testwe accelerated expansion null tests gaussian process
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A New Dynamics Expansion Mechanism for Plasma during Pulsed Laser Deposition 被引量:1
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作者 谭新玉 张端明 +4 位作者 冯笙琴 李智华 刘高斌 房然然 孙敏 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第1期198-201,共4页
The dynamics expansion mechanisms for plasma plume generated by pulsed laser radiation are studied in detail, taking account of plasma ionization effect. Based on the consideration of local conservations of mass, mome... The dynamics expansion mechanisms for plasma plume generated by pulsed laser radiation are studied in detail, taking account of plasma ionization effect. Based on the consideration of local conservations of mass, momentum, collected as the assumption that plasma can be viewed as compressible ideal fluid and high temperature-high pressure ideal gas, we develop a new dynamics expansion mechanism for plasma produced by pulsed laser radiation. Using the analytical method, the space number density and pressure evolvement of plasma in cylindrical coordinate are obtained, the dynamics evolvement equations are also derived. The results from the present model indicate that the plasma dynamic expansion behaviour can be evidently influenced by the ionization fraction η. Its effect is similar to a new dynamic source for plasma expansion and increases the expansion acceleration in all directions. The predictions of the expansion of the plasma is affected by the temperature, the average atoms mass and the ionization degree of the plasma are consistent with the experimental results. 展开更多
关键词 DIAMOND-LIKE CARBON ACCELERATED expansion ABLATED MATERIALS SOLID-SURFACE FILMS GAS PLUME
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On a Quantum Gravity Fractal Spacetime Equation: QRG ≃HD + FG and Its Application to Dark Energy—Accelerated Cosmic Expansion 被引量:1
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2016年第8期729-736,共8页
The paper suggests that quantum relativistic gravity (QRG) is basically a higher dimensionality (HD) simulating relativity and non-classical effects plus a fractal Cantorian spacetime geometry (FG) simulating quantum ... The paper suggests that quantum relativistic gravity (QRG) is basically a higher dimensionality (HD) simulating relativity and non-classical effects plus a fractal Cantorian spacetime geometry (FG) simulating quantum mechanics. This more than just a conceptual equation is illustrated by integer approximation and an exact solution of the dark energy density behind cosmic expansion. 展开更多
关键词 Fractal Cantorian Spacetime Quantum Relativity Superstrings Transfinite Set Theory Extra Spacetime Dimensions Quantum Physics Dark Energy Accelerated Cosmic expansion Cosmic Topology Hyperbolic Geometry E-Infinity Theory Post Modernistic Physics
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The Accelerated Expansion of the Universe
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期407-410,共4页
We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift ... We use experimental data from Distant Type 1a Supernovae to calculate the Observed Magnitude (m - M) which is the Apparent Magnitude (m) minus the Absolute Magnitude (M) for different values of the Redshift z which gives us the Distance Modulus. Then, we calculate the average velocity and average acceleration for different z values and plot them as a function of time. The expansion of the space of our 3-D Universe is exponential and it will end with a Big Bang as four 3-D Universes of which we are one will come together to form one 4-D expanding spatial Universe. 展开更多
关键词 Distance Modulus REDSHIFT Accelerated expansion Exponentially Expanding Space Big Bang
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Friedmann-Like Cosmological Equations for the Accelerated Expansion of the Universe
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作者 G. Alagar Ramanujam 《Journal of Modern Physics》 2020年第7期996-1004,共9页
In recent papers [1] [2] [3], we framed suitable axioms for Space called Super Space by Wheeler [4]. Using our axioms in Newtonian formalism and considering the density of the universe to be constant in time, we showe... In recent papers [1] [2] [3], we framed suitable axioms for Space called Super Space by Wheeler [4]. Using our axioms in Newtonian formalism and considering the density of the universe to be constant in time, we showed in the above references that at t = 0 the radius of the universe need not be zero. And thus, we avoided the problem of singularity. We further showed that the Hubble factor is no longer constant in time and goes on decreasing as confirmed by experiments. We pointed out in the above references that Space is the source of dark energy which is responsible for the accelerated expansion of the universe. With a view to improving the above-mentioned results quantitatively, in this paper, we are discussing the consequences of our axioms using Einstein’s field equations of general theory of relativity. Friedmann-like Cosmological equations with Dark Energy built-in are derived. This derivation is obtained using Robertson-Walker line element and by introducing a suitable expression for Energy-Momentum tensor in terms of matter and Dark energy contents of the universe. The solutions of our cosmological equations obtained here, show that the radius of the universe cannot reach zero but has a minimum value and there is also maximum value for the radius of the universe. The inflationary expansion of the very early universe emerges from our theory. 展开更多
关键词 Axioms for Space Dark Energy Seed of the Universe Einstein’s Field Equations Space (Vacuum) Energy Accelerated expansion
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The Accelerated Expansion of the Universe in the Light of the Maximum Ordinality Principle
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第2期585-602,共18页
The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in pa... The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in parallel” to the tradition-al ones, such as those based, for example, on the hypotheses of “Dark Matter” and “Dark Energy”, or better as a “com-possible” perspective, because it is not understood as being “exclusive”. In fact, it is an approach that, when con-firmed by experimental results, always keeps its validity from an “operative” point of view. This is because, in analogy to the traditional perspectives, on the basis of Popper’s Falsification Principle the corresponding “Generative” Logic on which it is based has not the property of the perfect induction. The basic difference then only consists in the fact that the Evolution of the Universe is now modeled by considering the Universe as a Self-Organizing System, which is thus analyzed in the light of the Maximum Ordinality Principle. 展开更多
关键词 Accelerated expansion of the Universe Maximum Ordinality Principle Incip-ient Differential Calculus
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The Reshaping of the Eurasian Regional Order and the SCO’s Unique Role in It
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作者 Sun Zhuangzhi 《Contemporary World》 2025年第5期2-7,共6页
With accelerated expansion,the Shanghai Cooperation Organization(SCO)has extended its geographical reach to the vast Eurasian region,where the balance of power has undergone profound changes since the end of the Cold ... With accelerated expansion,the Shanghai Cooperation Organization(SCO)has extended its geographical reach to the vast Eurasian region,where the balance of power has undergone profound changes since the end of the Cold War,showing instability and uncertainty.The type of order that can emerge in a region depends on the effectiveness of governance and the power structures and systems built upon it.The SCO advocates a brand new philosophy of cooperation that transcends the traditional mentality of international relations,forging a new model of multilateral collaboration.The SCO has vigorously participated in improving regional governance and is thus playing an increasingly important and unique role in reshaping the Eurasian regional order. 展开更多
关键词 SCO Shanghai Cooperation Organization accelerated expansion balance power power structures systems reshaping Eurasian regional order geographical reach
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Non-Rotating Black Holes, Dark Matter and Dark Energy in a Unifying Theory
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作者 Antonio Holdefer 《Journal of Applied Mathematics and Physics》 2021年第7期1560-1582,共23页
The theory here developed, makes use of the decomposition of matter (mass) in different spatial frequencies k’s using spatial Fourier transforms, and the posterior use of modified inverse Fourier transforms to constr... The theory here developed, makes use of the decomposition of matter (mass) in different spatial frequencies k’s using spatial Fourier transforms, and the posterior use of modified inverse Fourier transforms to construct an accurate description of the classical Newtonian gravitational field. Introducing the concept of quantization of the spatial frequency <em>k</em>, which means allowing only discrete values, such as <em>k<sub>m</sub></em>, 2<em>k<sub>m</sub></em>, 3<em>k<sub>m</sub></em>, leads to the appearance of extra gravitational force regions that occur at distances equally spaced apart in 2π/<em>k<sub>m</sub></em>. These areas of extra gravitational force decrease inscribed in an inverse of the distance envelope (1/<em>r</em>). The value of 2π/<em>k<sub>m</sub></em> can be adjusted to be of the order of kiloparsec (kpc), being this way a plausible explanation for the effect of the dark matter since this causes practically flat rotation curves for most of the galaxies. As these regions of extra gravitational force also have adjacent areas of negative values (repulsive gravitational force), it is possible to show that any mass placed in the gravitational field far from the galaxy center will acquire, on average, a null acceleration, thereby remains the “light push,” or in other words, the “mean luminosity density” between galaxies as an explanation for the accelerating expansion of the universe, today being considered mainly due to dark energy. Along with the article, it is showed that the effect of light push is sufficient to explain the expansion of the universe. The present work also explains the nonlinear behavior of gravitational fields near massive objects such as blackholes, not contradicting the theory of general relativity, instead giving a complementary description of how black holes work, even describing the gravitational field internally to it, which is not available in the GR theory. 展开更多
关键词 Black Holes Dark Matter Dark Energy Motion Energy accelerating expansion of the Universe
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Cantorian-Fractal Kinetic Energy and Potential Energy as the Ordinary and Dark Energy Density of the Cosmos Respectively 被引量:4
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作者 Mohamed S. El Naschie 《Natural Science》 2016年第12期511-540,共30页
In a one-dimension Mauldin-Williams Random Cantor Set Universe, the Sigalotti topological speed of light is  where . It follows then that the corresponding topological acceleration must be a golden mean downscali... In a one-dimension Mauldin-Williams Random Cantor Set Universe, the Sigalotti topological speed of light is  where . It follows then that the corresponding topological acceleration must be a golden mean downscaling of c namely . Since the maximal height in the one-dimensional universe must be where is the unit interval length and note that the topological mass (m) and topological dimension (D) where m = D = 5 are that of the largest unit sphere volume, we can conclude that the potential energy of classical mechanics translates to . Remembering that the kinetic energy is , then by the same logic we see that  when m = 5 is replaced by for reasons which are explained in the main body of the present work. Adding both expressions together, we find Einstein’s maximal energy . As a general conclusion, we note that within high energy cosmology, the sharp distinction between potential energy and kinetic energy of classical mechanics is blurred on the cosmic scale. Apart of being an original contribution, the article presents an almost complete bibliography on the Cantorian-fractal spacetime theory. 展开更多
关键词 Potential Dark Energy Kinetic Ordinary Energy Motion as Illusion Zenonparadoxa E-Infinity Theory Noncommutative Geometry Topological Acceleration Cantorian Universe Accelerated Cosmic expansion
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On a Fractal Version of Witten’s M-Theory 被引量:12
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第2期135-144,共10页
Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine t... Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine the measured ordinary energy density of the cosmos which turns out to be intimately linked to the new theory’s fractal dimension via non-integer irrational Lorentzian-like factor: where is Hardy’s probability of quantum entanglement. Consequently, the energy density is found from a limiting classical kinetic energy to be Here, is ‘tHooft’s renormalon of dimensional regularization. The immediate logical, mathematical and physical implication of this result is that the dark energy density of the cosmos must be in astounding agreement with cosmic measurements and observations. 展开更多
关键词 M-THEORY E-Infinity Theory Hardy’s Quantum Entanglement Transfinite Turing Computer Dark Energy Accelerated Cosmic expansion Noncommutative Geometry Superstring Theory Scale Relativity Cantorian-Fractal Spacetime Witten’s Theory ‘tHooft Renormalon Pure Gravity Penrose Tiling
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Negative Norms in Quantized Strings as Dark Energy Density of the Cosmos 被引量:1
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 CAS 2016年第2期63-67,共5页
The present short paper is concerned with accurate explanation as well as quantification of the so called missing dark energy of the cosmos. It was always one of the main objectives of any successful general theory of... The present short paper is concerned with accurate explanation as well as quantification of the so called missing dark energy of the cosmos. It was always one of the main objectives of any successful general theory of high energy particle physics and quantum cosmology to keep non-physical negative norms, the so called ghosts completely out of that theory. The present work takes the completely contrary view by admitting these supposedly spurious states as part of the physical Hilbert space. It is further shown that rethinking the ghost free condition with the two critical spacetime dimensions D<sub>1</sub> = 26 and D<sub>2</sub> = 25 together with the corresponding intercept a<sub>1</sub> = 1 and a<sub>2</sub> ≤ 1 respectively and in addition imposing, as in Gross et al. heterotic superstrings, an overall 496 dimensional exceptional Lie symmetry group, then one will discover that there are two distinct types of energy. The first is positive norm ordinary energy connected to the zero set quantum particles which is very close to the measured ordinary energy density of the cosmos, namely E(O) = mc<sup>2</sup>/22. The second is negative norm (i.e. ghost) energy connected to the empty set quantum wave and is equal to the conjectured dark energy density of the cosmos E(D) = mc<sup>2</sup> (21/22) presumed to be behind the observed accelerated cosmic expansion. That way we were able to not only explain the physics of dark energy without adding any new concepts or novel additional ingredients but also we were able to compute the dark energy density accurately and in full agreement with measurements and observations. 展开更多
关键词 Negative Norms Quantum Ghosts Dark Energy Accelerated Cosmic expansion SUPERSTRINGS Quantum Field Theory Cantorian-Fractal Spacetime Einstein Relativity Non-Fictional Spurions
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Quantum Dark Energy from the Hyperbolic Transfinite Cantorian Geometry of the Cosmos 被引量:1
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作者 Mohamed S. El Naschie 《Natural Science》 2016年第3期152-159,共8页
The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-pa... The quintessence of hyperbolic geometry is transferred to a transfinite Cantorian-fractal setting in the present work. Starting from the building block of E-infinity Cantorian spacetime theory, namely a quantum pre-particle zero set as a core and a quantum pre-wave empty set as cobordism or surface of the core, we connect the interaction of two such self similar units to a compact four dimensional manifold and a corresponding holographic boundary akin to the compactified Klein modular curve with SL(2,7) symmetry. Based on this model in conjunction with a 4D compact hy- perbolic manifold M(4) and the associated general theory, the so obtained ordinary and dark en- ergy density of the cosmos is found to be in complete agreement with previous analysis as well as cosmic measurements and observations such as WMAP and Type 1a supernova. 展开更多
关键词 Dark Energy Accelerated Cosmic expansion Hyperbolic Geometry Fractal Geometry Transfinite set Theory ‘tHooft Dimensional Regularization Hardy’s Quantum Entanglement Davis Hyperbolic Manifold Compactified Klein Modular Curve Fractal Counting Lie Symmetry Groups Stein Spaces
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Kähler Dark Matter, Dark Energy Cosmic Density and Their Coupling 被引量:2
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2016年第14期1953-1962,共11页
We utilize homology and co-homology of a K3-K&#228;hler manifold as a model for spacetime to derive the cosmic energy density of our universe and subdivide it into its three fundamental constituents, namely: 1) or... We utilize homology and co-homology of a K3-K&#228;hler manifold as a model for spacetime to derive the cosmic energy density of our universe and subdivide it into its three fundamental constituents, namely: 1) ordinary energy;2) pure dark energy and 3) dark matter. In addition, the fundamental coupling of dark matter to pure dark energy is analyzed in detail for the first time. Finally, the so-obtained results are shown to be in astounding agreement with all previous theoretical analysis as well as with actual accurate cosmic measurements. 展开更多
关键词 Kähler Topology Dark Matter E-INFINITY Super Strings Golden Mean Computer Kerr Black Hole Geometry Accelerated Cosmic expansion Fractal Cantorian Spacetime
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Charged Randall-Sundrum Braneworld Type Ⅱ with Higher Order Curvature Corrections from Superstring Arguments and Dominated by Quintessence
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作者 EL-NABULSI Ahmad Rami 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期869-881,共13页
We discuss a new class of RSII braneworld cosmology exhibiting accelerated expansion and dominated by quintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to dece... We discuss a new class of RSII braneworld cosmology exhibiting accelerated expansion and dominated by quintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to deceleration epoch to acceleration and effective quintessence era) may naturally occur in such unified theory for some classes of inverse scalar potentials. Besides a decaying effective cosmological constant, the model incorporates an increasing black hole mass, an increasing Maxwellian electrical charge with cosmic time and a time-dependent brahe tension. The cosmological model exhibits several features of cosmological and astrophysical interest for both the early and late universe consistent with recent observations, in particular the ones concerned with the gravitational constants, black holes masses and charges and variation of the gauge coupling parameters with cosmic time. One interesting mark of the constructed model concerns the fact that a black hole mass surrounded by quintessence energy may increase with time even if the horizon disappears. 展开更多
关键词 brane world RSII cosmology higher order curvature corrections black hole black strings effective cosmological constant Maxwellian charge QUINTESSENCE accelerated expansion
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Oscillating Flat FRW Dark Energy Dominated Cosmology from Periodic Functional Approach
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作者 EL-NABULSI Ahmad Rami 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期16-20,共5页
I discuss the modification of Einstein's Theory of General Relativity based on a periodic functional approach. In this new approach, a corrected periodic gravitational coupling constant arises and plays the role of p... I discuss the modification of Einstein's Theory of General Relativity based on a periodic functional approach. In this new approach, a corrected periodic gravitational coupling constant arises and plays the role of periodic damping term acting on the theory. It is found that it is achievable to have an oscillating universe dominated by dark energy and expanding aceeleratedly in time. 展开更多
关键词 corrected gravitational coupling constant dark energy cosmological constant oscillating universe accelerated expansion
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Matter Loops Corrected Modified Gravity in Palatini Formulation
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作者 MENG Xin-He WANG Peng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期275-278,共4页
Recently,corrections to the standard Einstein Hilbert action were proposed to explain the current cosmicacceleration in stead of introducing dark energy.In the Palatini formulation of those modified gravity models,the... Recently,corrections to the standard Einstein Hilbert action were proposed to explain the current cosmicacceleration in stead of introducing dark energy.In the Palatini formulation of those modified gravity models,thereis an important observation due to Arkani Hamed:matter loops will give rise to a correction to the modified gravityaction proportional to the Ricci scalar of the metric.In the presence of such a term,we show that the current formsof modified gravity models in Palatini formulation,specifically,the 1/R gravity and in R gravity,will have phantoms.Then we study the possible instabilities due to the presence of phantom fields.We show that the strong instability inthe metric formulation of 1/R gravity indicated by Dolgov and Kawasaki will not appear and the decay timescales forthe phantom fields may be long enough for the theories to make sense as effective field theory.On the other hand,if wechange the sign of the modification terms to eliminate the phantoms,some other inconsistencies will arise for the variousversions of the modified gravity models.Finally,we comment on the universal property of the Palatini formulation ofthe matter loops corrected modified gravity models and its implications. 展开更多
关键词 modified gravity accelerated cosmic expansion loop correction and dark energy
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Gravity, Density, Acceleration, and the Constants of Nature
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期210-215,共6页
The component of light in the 3<sup>rd</sup> dimension decreases as light enters the 4<sup>th</sup> dimension created by a Black Hole. Hence particles moving in 3-D space will emit radiation du... The component of light in the 3<sup>rd</sup> dimension decreases as light enters the 4<sup>th</sup> dimension created by a Black Hole. Hence particles moving in 3-D space will emit radiation due to the Cherenkov Effect. Gravity and acceleration are the same according to Einstein’s Equivalence Principle. Density also has the same effect as gravity because gravity attracts matter thereby increasing matter density. The laws of Physics and all the constants of nature such as the Speed of light, Planck’s constant, the Gravitational constant, and so on are a function of the dimension of the space they are in since the vacuum energy density of each higher dimension is greater. We analyze the graph of the accelerated expansion of the Universe to calculate the acceleration for small Redshift z and predict what will happen for larger z values. 展开更多
关键词 DENSITY Speed of Light Time Dimensions MULTIVERSE Accelerated expansion of the Universe
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Including Space-Time in the Extended Group Cl3* of Relativistic Form-Invariance
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作者 Claude Daviau Jacques Bertrand 《Journal of Modern Physics》 CAS 2022年第8期1147-1156,共10页
The inclusion of space-time in the extended group of relativistic form-invariance, Cl<sub>3</sub>*</sup>, is specified as the inclusion of the whole space-time manifold in this multiplicative Lie gro... The inclusion of space-time in the extended group of relativistic form-invariance, Cl<sub>3</sub>*</sup>, is specified as the inclusion of the whole space-time manifold in this multiplicative Lie group. First physical results presented here are: the geometric origin of the time arrow, a better understanding of the non-simultaneity in optics and a mainly geometric origin for the universe expansion, and its recent acceleration. 展开更多
关键词 Space-Time Manifold Invariance Group Standard Model Acceleration of expansion
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Variable Speed of Light with Time and General Relativity
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作者 Giuseppe Pipino 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期742-760,共19页
In a previous article entitled: “Evidences for varying speed of light with time” [1], a series of observational evidence was presented in favor of the hypothesis that the speed of light varies with time according to... In a previous article entitled: “Evidences for varying speed of light with time” [1], a series of observational evidence was presented in favor of the hypothesis that the speed of light varies with time according to the relationship d<i>c</i>/d<i>t</i> = -<i>Hc</i>, where <i>H</i> is the Hubble constant which is considered a universal constant. In this paper we propose to elaborate on the observational evidence supporting the hypothesis, and to probe the consequences of this relationship on General Relativity. Also we will provide a theoretical justification of the previous relationship and we will show how from it we can deduce galactic velocity curves. We can deduce the important empirical Tully-Fisher relation linking these curves to the baryonic mass of the galaxy and we can justify the apparent accelerated expansion of the universe without intervening elusive entities such as dark matter and dark energy. 展开更多
关键词 Abnormal Acceleration Modified Newtonian Dynamic Tully-Fisher Relation REDSHIFT Hubble’s Law Dark Matter Dilation of Light Curves of Supernovae Ia Acceleration of expansion of Universe General Relativity
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Standard Model Review and a New 5D Multi-Brane Proposition
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作者 Jami Hossain 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期195-227,共33页
Based on a comprehensive review of mainly the non-quantum aspects of the standard model of cosmology, the 5 dimensional models, and the analysis here, we propose a 5 dimensional model with expanding 4D multi-branes. A... Based on a comprehensive review of mainly the non-quantum aspects of the standard model of cosmology, the 5 dimensional models, and the analysis here, we propose a 5 dimensional model with expanding 4D multi-branes. A review of the standard model in the context of many new developments and discoveries in cosmology in the recent times, such as the accelerated expansion of the universe, Plank cosmic microwave measurements, dark energy survey, Hubble tension etc. tends to indicate that the standard model is essentially a patchwork of different theoretical models that have been pieced together in an attempt to explain different aspects of the astrophysical observations, which do not necessarily emanate from a full end-to-end understanding of a physical process. The purpose of each individual theoretical piece such as “inflation” is limited to providing an explanation to the problem area or a gap in our understanding. A number of new theories such as the five-dimensional universe, the bulk and brane, extended theories of gravity, and conformal cyclic cosmology offer alternate ways of addressing the existential aspects of the universe but these models too remain hypothetical with shortcomings and a lack of conclusive evidence. The model proposed by us, presents a way forward in addressing dark matter and dark energy as manifestations of the multiple underlying branes in the aftermath of the big-bang. In the process, we present a theorem of the dimensionality of the expanding universe, which necessitates the need for at least one more dimension in addition to the 4 dimensions of spacetime. While carrying out the review of the standard model, we present new analysis and facts that strengthen the case for the 5<sup>th</sup> dimension. According to the multi-brane hypothesis presented here, our observed universe could be one of the many branes, and it is more likely than not that in the <i>aftermath</i> of the big-bang that generated <i>our brane</i>, more branes were generated, which further points towards a much more prolonged big-bang event than what has been the perception so far. 展开更多
关键词 BIG-BANG Dark Matter Dark Energy Cosmological Constant Standard Model BRANE 5D Universe Accelerated expansion
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