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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 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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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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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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On Some Mathematical Connections between the Cyclic Universe, Inflationary Universe, p-Adic Inflation, p-Adic Cosmology and Various Sectors of Number Theory
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作者 Michele Nardelli 《Journal of Modern Physics》 2024年第11期1869-1958,共90页
This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmo... This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmology. In Section 2, we have described some equations concerning cosmic evolution in a Cyclic Universe. In Section 3, we have described some equations concerning the cosmological perturbations in a Big Crunch/Big Bang space-time, the M-theory model of a Big Crunch/Big Bang transition and some equations concerning the solution of a braneworld Big Crunch/Big Bang Cosmology. In Section 4, we have described some equations concerning the generating ekpyrotic curvature perturbations before the Big Bang, some equations concerning the effective five-dimensional theory of the strongly coupled heterotic string as a gauged version of N=1five-dimensional supergravity with four-dimensional boundaries, and some equations concerning the colliding branes and the origin of the Hot Big Bang. In Section 5, we have described some equations regarding the “null energy condition” violation concerning the inflationary models and some equations concerning the evolution to a smooth universe in an ekpyrotic contracting phase with w>1. In Section 6, we have described some equations concerning the approximate inflationary solutions rolling away from the unstable maximum of p-adic string theory. In Section 7, we have described various equations concerning the p-adic minisuperspace model, zeta strings, zeta nonlocal scalar fields and p-adic and adelic quantum cosmology. In Section 8, we have shown various and interesting mathematical connections between some equations concerning the p-adic inflation, the p-adic quantum cosmology, the zeta strings and the brane collisions in string and M-theory. Furthermore, in each section, we have shown the mathematical connections with various sectors of Number Theory, principally the Ramanujan’s modular equations, the Aurea Ratio and the Fibonacci’s numbers. 展开更多
关键词 String Theory M-THEORY Cyclic cosmology p-Adic and Adelic Analysis Number Theory Ramanujan’s Modular Equations
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Predicting Dark Energy Survey Results within the Haug-Tatum Cosmology Model
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作者 Eugene Terry Tatum Espen Gaarder Haug 《Journal of Modern Physics》 2024年第12期2220-2227,共8页
Given the pending completion and publication of the final Dark Energy Survey (DESI) results, this letter presents the corresponding predictions of the Haug-Tatum cosmology (HTC) model. In particular, we show in tabula... Given the pending completion and publication of the final Dark Energy Survey (DESI) results, this letter presents the corresponding predictions of the Haug-Tatum cosmology (HTC) model. In particular, we show in tabular and graphic form the “dark energy decay” curve which the HTC model predicts for cosmological redshifts covering the range of 0 - 2.0 z. Furthermore, we present the HTC model distance-vs-redshift curve in comparison to the three very different curves (for luminosity distance, angular diameter distance, and co-moving distance) calculated within the Lambda-CDM model. Whether the expansion of our universe is actually undergoing slight acceleration or the finely-tuned cosmic coasting at constant velocity of Rh = ct models, including HTC, will hopefully soon be answered by the many pending observational studies. 展开更多
关键词 Haug-Tatum cosmology Dark Energy Lambda-CDM cosmology Cosmological Redshift Hubble Parameter Upsilon Constant DESI Rh = ct cosmology
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Classical Cosmology III. Modified Tired Light and Distance Modulus for Supernovae
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作者 Lorenzo Zaninetti 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1538-1550,共13页
We analyze a simple model for tired light in a cosmological environment, a generalized model, and a spectroscopic model. The three models are tested on different compilations for the distance modulus of supernovae. Th... We analyze a simple model for tired light in a cosmological environment, a generalized model, and a spectroscopic model. The three models are tested on different compilations for the distance modulus of supernovae. The tests are negative for the simple tired light and the spectroscopic models, but positive for the generalized tired light model. The percentage error of the distance modulus for the generalized tired light model compared with the distance modulus of standard cosmology is less than one percent over the considered ranges in redshift. 展开更多
关键词 Galaxy Groups Large Scale Structure of the Universe 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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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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The Fate of Supersymmetry in Quantum Field Theories
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期609-620,共12页
We analyze the significance of supersymmetry in two topological models and the standard model (SM). We conclude that the two topological field theory models favor hidden supersymmetry. The SM superpartners, instead, h... We analyze the significance of supersymmetry in two topological models and the standard model (SM). We conclude that the two topological field theory models favor hidden supersymmetry. The SM superpartners, instead, have not been found. 展开更多
关键词 Topological Field Theory SUPERSYMMETRY Chern-Simons Model
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Gravitational Wave Detection Technology Development and Its Contribution to Cosmology
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作者 Yiqi Xu 《Journal of Applied Mathematics and Physics》 2024年第11期3697-3705,共9页
Gravitational wave detection has ushered in a new era of observing the universe, providing humanity with a novel window for cosmic cognition. This theoretical study systematically traces the developmental trajectory o... Gravitational wave detection has ushered in a new era of observing the universe, providing humanity with a novel window for cosmic cognition. This theoretical study systematically traces the developmental trajectory of gravitational wave detection technology and delves into its profound impact on cosmological research. From Einstein’s prediction in general relativity to LIGO’s groundbreaking discovery, the article meticulously delineates the key theoretical and technological milestones in gravitational wave detection, with particular emphasis on elucidating the principles and evolution of core detection technologies such as laser interferometers. The research thoroughly explores the theoretical application value of gravitational waves in verifying general relativity, studying the physics of compact celestial bodies like black holes and neutron stars, and precisely measuring cosmological parameters. The article postulates that gravitational wave observations may offer new research perspectives for addressing cosmological conundrums such as dark matter, dark energy, and early universe evolution. The study also discusses the scientific prospects of combining gravitational wave observations with electromagnetic waves, neutrinos, and other multi-messenger observations, analyzing the potential value of this multi-messenger astronomy in deepening cosmic cognition. Looking ahead, the article examines cutting-edge concepts such as space-based gravitational wave detectors and predicts potential developmental directions for gravitational wave astronomy. This research not only elucidates the theoretical foundations of gravitational wave detection technology but also provides a comprehensive theoretical framework for understanding the far-reaching impact of gravitational waves on modern cosmology. 展开更多
关键词 Gravitational Waves Detection Technology cosmology Multi-Messenger Astronomy General Relativity
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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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Time Dilation Cosmology 3: Mathematical Proof of the 3 Temporal and 2 Spatial Acceleration Factors
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第12期2228-2237,共10页
This is the fifth paper in a series on Time Dilation Cosmology, TDC. TDC is an eternal holographic model of the universe based on time dilation that ties astrophysics to quantum physics and resolves all the conundrums... This is the fifth paper in a series on Time Dilation Cosmology, TDC. TDC is an eternal holographic model of the universe based on time dilation that ties astrophysics to quantum physics and resolves all the conundrums in astrophysics and serves as a model for the unified field. In the author’s previous four TDC papers, it was demonstrated that all gravitationally induced velocities are compensation for the apparent difference in the rates of time, “dRt”, due to mass/energy densities, and, vice-versa, in all force-induced velocities the dRt is compensation for the velocity, so the uniform evolution of the continuum at c is maintained at the invariant 1 s/s rate of time of the universe as a whole. These compensations make it impossible for an event to lag behind or get ahead of the evolving continuum. When the author did the first velocity formula derivations in “General Relativity: Effects in Time as Causation” [1], the author felt the explanations for the appearance of the 2spatial and the 3temporal acceleration factors in the formulas were correct, but poorly explained and incomplete. This paper is a proof of the temporal and spatial acceleration factors used in the time dilation-based velocity formula derivations in the Time Dilation Cosmology model. 展开更多
关键词 Mathematical Proof Time Dilation cosmology Acceleration Factors
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Dual Instinct and Structural Theories: DSM-5-TR
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作者 Lawrence Greenman 《Open Journal of Psychiatry》 2024年第4期374-379,共6页
The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding de... The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding defence mechanisms are combined with biologically based stages of infant/child development and the functional entity of Structural Theory. This model of human nature is the applied to the diagnostic categories of DSM-5-TR. Objectives: To follow the innate Dual Instinct Theory from life to death and through Artificial Intelligence;connect it with biological stages of development of the Structural Theory and illustrate its manifestations in DSM-5-TR classifications. Method: Review of selected published literature. Applying the principle of focus and cognition of informed clinical observation of innate drive derivatives in conjunction with The Structural Theory. Both theories are functional entities with no structures involved. Sigmund Freud’s biologically based stages of development;oral, anal, genital pubic, adult, and geriatric along with a variety of unconscious, automatic, and persistent defense mechanisms are selectively folded into diagnosis listed in the manual. 展开更多
关键词 Dual Instincts Structural Theory Stages of Development Drive Derivatives Mechanisms of Defense
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A Study on Inflation Theories and Turkey’s Inflation Problem
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作者 SıtkıSelim Dolanay 《Management Studies》 2024年第5期309-322,共14页
In the Turkish Economy,with the policies of opening up to the outside world and transition to a free market economy in the 1980s,there have been radical changes in the structure of the economy and the prices of all go... In the Turkish Economy,with the policies of opening up to the outside world and transition to a free market economy in the 1980s,there have been radical changes in the structure of the economy and the prices of all goods and services have begun to be determined by the market under market conditions.In the 1980s,which can be called the transition process to a free market economy and open economy,on the one hand,efforts were made to privatize state institutions in order to withdraw the state from economic life and to ensure that the prices of goods and services were determined under free market conditions,while on the other hand,efforts were made to grant freedom to foreign trade.While these two main issues were being realized,the import substitution industrialization strategy was abandoned and an export-based growth model was started to be implemented.The last step of this opening up and liberalization process was realized with the decision numbered 32 in 1989.With the liberalization of capital movements in the 1990s,we can say that economic growth and development was attempted to be achieved through hot money inflows rather than direct foreign investments.This orientation made the economy more vulnerable to crises,and for the first time,a crisis occurred in the form of the 1994 economic crisis,which was understood to be caused by hot money.The 1994 economic crisis was attempted to be overcome by providing state guarantees for bank deposits and applying high interest rates.Thus,it is noteworthy that high inflation was experienced in the period leading up to the 2001 economic crisis.Indeed,while the increase in the wholesale price index rarely remained below 30%on an annual basis between 1980 and 1990,increases of 50%and 60%began to be seen.However,the period between 1990 and 2000 was a period in which higher inflation rates were encountered.As a result of the environment created in the 1990s,we can say that the financial crisis experienced in 2001 deepened into an economic crisis and that this crisis had economic and political effects.Although there have been many economic crises in the history of the Republic,this crisis is considered to be the most deeply effective.While the crisis was overcome with the stand-by agreement made by the IMF and the announced Transition to a Strong Economy program,the economy began to grow rapidly with the ease of use of foreign resources,and the existence of political stability seems to have ensured that this economic growth process continued uninterruptedly except for 2009.A decrease was also experienced in inflation rates.After 2015,inflation rates began to rise again,and although negative economic growth rates were experienced between the 3rd quarter of 2018 and the 3rd quarter of 2019 during the exchange rate shock period in 2018,we can say that this was not effective enough to turn annual average growth rates into negatives.The exchange rate shock experienced in November 2021 both caused changes in economic policies and the adoption of new policies,and seems to have led to an economic crisis wave caused by the large increase in inflation rates.Within this framework,a post-Keynesian policy of combating inflation has been implemented,and with the new economic policies announced in June 2023,the Central Bank has gradually increased policy interest rates and started to implement tight monetary policy in cooperation with the Ministry of Treasury and Finance,and we can say that a new phase has been entered in the post-Keynesian policy of combating inflation.However,in our opinion,it is necessary to determine well where inflation originates from and what ensures its continuation.In this context,Turkey’s inflation problem will be analyzed by utilizing the views of post-Keynesians on inflation and the profit-push inflation approach. 展开更多
关键词 Turkish economy free market economy export-based growth model inflation theories post-Keynesian approach to inflation profit-push inflation approach
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Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第7期2421-2451,共31页
Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The ... Complex model, say C3, of “para-space” as alternative to the real M4 Minkowski space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous works on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) kind of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The key point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the kinematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared. 展开更多
关键词 Special Relativity’s Hyperbolic Versus Circular Versions Galilean Kinematics Partial Equivalence of SR and Newton’s theories Algebra of Relativistic and the Corresponding Galilean Velocities
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Chinese Education Modernization:A Case Study on Ideological and Political Theories Teaching in All Courses with Organic Integration of Cultural Literacy and Political Education
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作者 Zongyu Gan 《Journal of Contemporary Educational Research》 2024年第5期172-176,共5页
Chinese education modernization is integral to Chinese modernization,and is of leading significance to the further advancement of Chinese modernization and the great rejuvenation of the Chinese nation.In this paper,ta... Chinese education modernization is integral to Chinese modernization,and is of leading significance to the further advancement of Chinese modernization and the great rejuvenation of the Chinese nation.In this paper,taking ideological and political theories teaching in all courses as an example,an attempt is made to organically integrate cultural literacy and political education under the vision of Chinese education modernization,and“gathers knowledge heritage in the dissemination of value and leads the values in the dissemination of knowledge,”thereby training students into highcaliber talents with good and all-round moral,intellectual,physical,aesthetical,and labor grounding. 展开更多
关键词 Chinese education modernization Ideological and political theories teaching in all courses EDUCATION
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掺杂磷烯二维纳米材料对草甘膦吸附机理的研究
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作者 王群 周乃武 +5 位作者 单正莉 覃庆雨 刘钰佳 王梅 梅青刚 孙玉希 《原子与分子物理学报》 CAS 北大核心 2025年第4期58-64,共7页
草甘膦是世界上普遍使用的除草剂之一,被广泛使用在农田和非农田杂草的防治.由于草甘膦类除草剂的大范围应用,其对动植物的危害性逐渐受到人们的关注.磷烯二维纳米材料与草甘膦之间相互作用机理的研究对草甘膦的检测及去除具有重大的意... 草甘膦是世界上普遍使用的除草剂之一,被广泛使用在农田和非农田杂草的防治.由于草甘膦类除草剂的大范围应用,其对动植物的危害性逐渐受到人们的关注.磷烯二维纳米材料与草甘膦之间相互作用机理的研究对草甘膦的检测及去除具有重大的意义.本研究将采用基于密度泛函理论方法考察本征及Al,Ca,Ti及Fe金属原子掺杂的磷烯对草甘膦的吸附,通过吸附能,差分电荷密度,布居电荷分析本征及金属原子掺杂磷烯对草甘膦的吸附机制,从分子和原子水平上研究它们之间的详细机理.研究结果有望为掺杂磷烯材料在草甘膦吸附方面的应用提供有意义的理论参考. 展开更多
关键词 磷烯 掺杂磷烯 草甘膦 密度泛函理论
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基于密度泛函理论纤维素热解机理热力学研究
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作者 周俊杰 陈曦 +1 位作者 汤松臻 李智聪 《原子与分子物理学报》 CAS 北大核心 2025年第5期1-6,共6页
为了探究纤维素的热解机理,参考相关的实验结果,以纤维素单体模化物为研究对象,采用密度泛函理论的方法,以b3lyp/6-31++g(d,p)为基,对纤维素单体热解反应生成乙醇醛和CO_(2)小分子的反应机理进行动力学研究.纤维素单体热解生成乙醇醛和C... 为了探究纤维素的热解机理,参考相关的实验结果,以纤维素单体模化物为研究对象,采用密度泛函理论的方法,以b3lyp/6-31++g(d,p)为基,对纤维素单体热解反应生成乙醇醛和CO_(2)小分子的反应机理进行动力学研究.纤维素单体热解生成乙醇醛和CO_(2)的反应路径为纤维素单体首先开环,之后裂解生成四糖片段M2和乙醇醛P1,能垒最高为339.1 kJ/mol,四糖片段M2经过脱水形成烯酮结构后再与水分子作用生成羧基,最后发生脱羧反应生成CO_(2),能垒较高为290.1 kJ/mol,不容易发生,整个过程放出98.9 kJ/mol的热量,并对路径反应物、中间体和过渡态进行几何构型全优化,过渡态的振动和频率计算,同时进行不同温度下(400 K、600 K、800 K、1000 K、1200 K)热解过程的热力学分析,对纤维素的热解机理研究将对生物质的热裂解机理研究有重要的意义. 展开更多
关键词 纤维素 热解 密度泛函理论 反应机理
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