期刊文献+
共找到32,535篇文章
< 1 2 250 >
每页显示 20 50 100
Gedankenexperiment for Modified ZPE and Planck’s “Constant”, h, in the Beginning of Cosmological Expansion, Partly Due to NLED
1
作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期180-184,共5页
We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Se... We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Seth Lloyd) as to what would be available initially due to a modified ZPE formalism. The ZPE formalism is modified as due to Matt Visser’s alternation of k (maximum) ~ 1/(Planck length), with a specific initial density giving rise to initial information content which may permit fixing the initial Planck’s constant, h, which is pivotal to the setting of physical law. The settings of these parameters depend upon NLED. 展开更多
关键词 ZPE Planck’s constant Gedankenexperiment NLED
下载PDF
Elementary Fermions: Strings, Planck Constant, Preons and Hypergluons
2
作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期82-100,共19页
Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism ... Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism which is proportional to Planck’s constant. This may be the result of two massless bosons (hypergluons) coupled by a preon (prequark) exchange. It also gives a physical explanation to the origin of the Planck constant, and origin of spin. 展开更多
关键词 FERMIONS Preons Hypergluons Strings Real Fields Planck constant INTERFERENCE SPIN
下载PDF
ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR
3
作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
下载PDF
Enriched Constant Elements in the Boundary Element Method for Solving 2D Acoustic Problems at Higher Frequencies
4
作者 Zonglin Li Zhenyu Gao Yijun Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2159-2175,共17页
The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models... The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models must meet the requirement of 6–10 elements per wavelength,using the conventional constant,linear,or quadratic elements.Therefore,a large storage size of memory and long solution time are often needed in solving higher-frequency problems.In this work,we propose two new types of enriched elements based on conventional constant boundary elements to improve the computational efficiency of the 2D acoustic BEM.The first one uses a plane wave expansion,which can be used to model scattering problems.The second one uses a special plane wave expansion,which can be used tomodel radiation problems.Five examples are investigated to showthe advantages of the enriched elements.Compared with the conventional constant elements,the new enriched elements can deliver results with the same accuracy and in less computational time.This improvement in the computational efficiency is more evident at higher frequencies(with the nondimensional wave numbers exceeding 100).The paper concludes with the potential of our proposed enriched elements and plans for their further improvement. 展开更多
关键词 Enriched boundary elements constant elements 2D acoustic problems higher frequency
下载PDF
The Extremal Universe Exact Solution from Einstein’s Field Equation Gives the Cosmological Constant Directly
5
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
下载PDF
Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations
6
作者 Legeng Yu Nan Yao +5 位作者 Yu-Chen Gao Zhong-Heng Fu Bo Jiang Ruiping Li Cheng Tang Xiang Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期299-305,I0008,共8页
Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite ano... Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes. 展开更多
关键词 Lithium batteries Graphite N-DOPING Electric double layer Molecular dynamics constant potential method Electrode potential
下载PDF
New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
7
作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum Mechanics Space Time Dark Matter A New Fundamental constant “K”
下载PDF
Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
8
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
下载PDF
The Planck Constant and Its Relation to the Compton Frequency
9
作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第1期168-180,共13页
The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new... The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new perspectives on the Planck constant should therefore be of interest. We demonstrate that the Planck constant also can be directly linked to the Compton frequency of one, which again is divided by the Compton frequency in one kg. If this is right, it means also the Planck constant is linked to quantization of matter, not only energy. However, as we will show the frequency of one when expressed in relation to kg will be observational time dependent. This means the missing mass gap surprisingly both is equal to the Planck mass, which is larger than any known particle and also it is linked to a very small mass that again is equal to what has been suggested as the photon mass in the existing literature. This new view could be an important step forward in understanding the physical nature of the Planck constant as well as the mass gap and even the rest mass of a photon. 展开更多
关键词 Planck constant Compton Frequency ELECTRON Proton Count
下载PDF
Introducing a 2nd Universal Space-Time Constant Can Explain the Observed Age of the Universe and Dark Energy
10
作者 Herman A. van Hoeve 《World Journal of Mechanics》 2024年第2期9-22,共14页
The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal ... The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal space-time constant, besides having a finite speed constant (speed of light in vacuum c). A finite universal age constant b is introduced. Namely, this paper shows that the changes in the Earth’s anomalistic year duration over time support the hypothesis of the age of the universe correlating with a maximum number of orbital revolutions constant. Neglecting the gravitational influence of other cosmological entities in the proximity of the Earth, the constant maximum number of revolutions is herewith determined solely by the Earth’s orbital revolutions around the Sun. The value of the universal age constant b is calculated to be around 13.8 billion orbital revolutions, derived out of an equation related to the changes in the Earth’s anomalistic year duration over time and the so-called Hubble tension. The above-mentioned calculated value b correlates well with the best fit to measured data of the cosmic microwave background radiation (CMBR) by the Planck spacecraft, the age of the observed universe is measured to be approximately 13.787 ± 0.020 billion years (2018 final data release). Developing a theory with this 2<sup>nd</sup> universal space-time constant b, being covariant with respect to the Lorentz transformations when time spans are large, gives results such as: A confirmation of the measured CMBR value of 13.787 ± 0.020 billion years. Correlating well with the observed expansion rate of the universe (dark energy). The universe’s expansion accelerating over the last four to five billion years. 展开更多
关键词 Anomalistic Year Orbital Revolution Hubble Tension Age of the Universe Cosmological constant Dark Energy Cosmic Microwave Background
下载PDF
A Solution to the Cosmological Constant Problem Using the Holographic Principle (A Brief Note)
11
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
下载PDF
Sliding modes of fault activation under constant normal stiffness conditions 被引量:1
12
作者 Chuanqing Zhang Jie Xu +3 位作者 Shengji Jin Guojian Cui Yuhang Guo Lingyu Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第5期1213-1225,共13页
Fault activation has been the focus of research community for years.However,the studies of fault activation remain immature,such as the fault activation mode and its major factors under constant normal stiffness(CNS)c... Fault activation has been the focus of research community for years.However,the studies of fault activation remain immature,such as the fault activation mode and its major factors under constant normal stiffness(CNS)conditions associated with large thickness of fault surrounding rock mass.In this study,the rock friction experiments were conducted to understand the fault activation modes under the CNS conditions.Two major parameters,i.e.the initial normal stress and loading rate,were considered and calibrated in the tests.To reveal the response mechanism of fault activation,the local strains near the fault plane were recorded,and the macroscopic stresses and displacements were analyzed.The testing results show that the effect of displacement-controlled loading rate is more pronounced under the CNS conditions than that under constant normal load(CNL)conditions.Both the normal and shear stresses drop suddenly when the stick-slip occurs.The decrease and increase of the normal stress are synchronous with the shear stress in the regular stick-slip scenario,but mismatch with the shear stress during the chaotic stick-slip process.The results are helpful for understanding the fault sliding mode and the prediction and prevention of fault slip. 展开更多
关键词 Fault activation Rock friction mechanics Sliding modes constant normal stiffness(CNS) Displacement-controlled loading rates ROCKBURST
下载PDF
Unity Formulas for the Coupling Constants and the Dimensionless Physical Constants
13
作者 Stergios Pellis 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期245-294,共50页
In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interact... In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interactions. We will find the formulas for the Gravitational constant. It will be presented that the gravitational fine-structure constant is a simple analogy between atomic physics and cosmology. We will find the expression that connects the gravitational fine-structure constant with the four coupling constants. Perhaps the gravitational fine-structure constant is the coupling constant for the fifth force. Also will be presented the simple unification of atomic physics and cosmology. We will find the formulas for the cosmological constant and we will propose a possible solution for the cosmological parameters. Perhaps the shape of the universe is Poincare dodecahedral space. This article will be followed by the energy wave theory and the fractal space-time theory. 展开更多
关键词 Fine-Structure constant Proton To Electron Mass Ratio Dimensionless Physical constants Coupling constant Gravitational constant Avogadro’s Number Fundamental Interactions Gravitational Fine-Structure constant Cosmological constant
下载PDF
Fundamental Physical Constants and Primary Physical Parameters
14
作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期190-209,共20页
Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, ... Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, the World-Universe Model (WUM) proposed a principally different depiction of the World as an alternative to the picture of the Big Bang Model. This article: 1) Gives the short history of Classical Physics before Special Relativity;2) Calculates Fundamental Physical Constants based on experimentally measured Rydberg constant, Electrodynamic constant, Electron Charge-to-Mass Ratio, and Planck constant;3) Discusses Electrodynamic constant and Speed of Light;4) Considers Dimensionless Fundamental Parameters (Dirac Large Number Q and Dimensionless Rydberg Constant α);5) Calculates Newtonian Constant of Gravitation based on the Inter-connectivity of Primary Physical Parameters;6) Makes a detailed analysis of the Self-consistency of Fundamental Physical Constants and Primary Physical Parameters through the prism of WUM. The performed analysis suggests: 1) Discontinuing using the notion “Vacuum” and its characteristics (Speed of Light in Vacuum, Characteristic Impedance of Vacuum, Vacuum Magnetic Permeability, Vacuum Electric Permittivity);2) Accepting the exact numerical values of Electrodynamic constant, Planck constant, Elementary charge, and Dimensionless Rydberg Constant α. WUM recommends the predicted value of Newtonian Constant of Gravitation in 2018 to be considered in CODATA Recommend Values of the Fundamental Physical Constants 2022. 展开更多
关键词 Classical Physics Fundamental Physical constants Electrodynamic constant Speed of Light Dirac Large Number Dimensionless Rydberg constant Newtonian constant of Gravitation Self-Consistency of Fundamental Physical constants
下载PDF
Polybenzoxazine/organosilicon composites with low dielectric constant and dielectric loss
15
作者 Manlin Yuan Xin Lu +4 位作者 Xiaoyun Ma Hao Lin Angui Lu Liyan Shao Zhong Xin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期241-249,共9页
The evolution of electronic communication technology raises higher requirements for low dielectric constant(low-k)materials.For this,a benzoxazine functional organosilicon(HP-aptes)with dense Si—O—Si crosslinking ne... The evolution of electronic communication technology raises higher requirements for low dielectric constant(low-k)materials.For this,a benzoxazine functional organosilicon(HP-aptes)with dense Si—O—Si crosslinking networks and large sterically hindered tert-butyl groups was prepared by the sol–gel method.Then,a series of polybenzoxazine composites(PPHP)were prepared from intrinsically low dielectric constant bis-functional benzoxazine monomer(P-aptmds)and HP-aptes.The double crosslinking networks of polybenzoxazine and organosilicon further increased the crosslinking density and decreased the dipole density of composites,which endowed the composites with enhanced low-k properties.When the content of HP-aptes is 30%(mass),the crosslinking density was 2.05×10^(-3)mol·cm^(-3),while that of PP-aptmds was 3.31×10^(-3)mol·cm^(-3).In addition,the dielectric constant and dielectric loss of PPHP composite at 1 MHz could reach 2.61 and 0.0056,respectively. 展开更多
关键词 POLYBENZOXAZINE ORGANOSILICON COMPOSITE Dielectric constant
下载PDF
On the Fine Structure and the Other Coupling Constants at the Planck Scale
16
作者 Paolo Christillin 《Journal of Modern Physics》 CAS 2023年第5期666-669,共4页
It is shown that the fine structure constant at Planck times tends to one as well as those of the weak and strong interactions. This results by constraining them at the Planck force. That seems to provide interesting ... It is shown that the fine structure constant at Planck times tends to one as well as those of the weak and strong interactions. This results by constraining them at the Planck force. That seems to provide interesting new results which confirm that at the beginning of space time (Planck scale) all fundamental forces converge to the same unit value. 展开更多
关键词 Fine Structure constant Fundamental Interactions Coupling constants Unification at Planck Scale
下载PDF
CONSTANT DISTANCE BOUNDARIES OF THE t-QUASICIRCLE AND THE KOCH SNOWFLAKE CURVE
17
作者 魏鑫 文志英 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期981-993,共13页
LetΓbe a Jordan curve in the complex plane and let Γ_(λ) be the constant distance boundary ofΓ.Vellis and Wu[10]introduced the notion of a(ζ,r_(0))-chordal property which guarantees that,whenλis not too large, ... LetΓbe a Jordan curve in the complex plane and let Γ_(λ) be the constant distance boundary ofΓ.Vellis and Wu[10]introduced the notion of a(ζ,r_(0))-chordal property which guarantees that,whenλis not too large, Γ_(λ) is a Jordan curve whenζ=1/2 and Γ_(λ) is a quasicircle when 0<ζ<1/2.We introduce the(ζ,r_(0),t)-chordal property,which generalizes the(ζ,r_(0))-chordal property,and we show that under the condition thatΓis(ζ,r_(0),√t)-chordal with 0<ζ<r_(0)^(1−√t)/2,there existsε>0 such that Γ_(λ) is a t-quasicircle once Γ_(λ) is a Jordan curve when 0<λ<ε.In the last part of this paper,we provide an example:Γis a kind of Koch snowflake curve which does not have the(ζ,r_(0))-chordal property for any 0<ζ<1/2,however Γ_(λ) is a Jordan curve whenλis small enough.Meanwhile,Γhas the(ζ,r_(0),√t)-chordal property with 0<ζ<r_(0)^(1−√t)/2 for any t∈(0,1/4).As a corollary of our main theorem, Γ_(λ) is a t-quasicircle for all 0<t<1/4 whenλis small enough.This means that our(ζ,r_(0),t)-chordal property is more general and applicable to more complicated curves. 展开更多
关键词 constant distance boundary t-quasicircle Koch snowflake curve
下载PDF
Precise measurement of 171Yb magnetic constants for 1S_(0)–3P_(0) clock transition
18
作者 张昂 田聪聪 +5 位作者 朱强 王兵 熊德智 熊转贤 贺凌翔 吕宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期184-188,共5页
We present a precise measurement of171Yb magnetic constants for 1S_(0)-3P_(0) clock transition. The background magnetic field is firstly compensated to < 1 m Gs(1 Gs = 10^(-4)T) through measuring the splitting of t... We present a precise measurement of171Yb magnetic constants for 1S_(0)-3P_(0) clock transition. The background magnetic field is firstly compensated to < 1 m Gs(1 Gs = 10^(-4)T) through measuring the splitting of two π transitins of171Yb clock transition at different compensation coils currents. Then, the splitting ratios of the π and σ components of171Yb clock transition at different bias magnetic fields are measured, and the first-order Zeeman coefficient is determined to beα = 199.49(5) Hz/Gs. The second-order Zeeman shifts at various bias magnetic fields are also measured through interleaved self-comparison in which the bias magnetic fields are modulated between high and low values. The second-order Zeeman coefficient is fitted to be β =-6.09(3) Hz/m T^(2), which is consistent with the result of NIST group. 展开更多
关键词 optical lattice clock ytterbium atoms Zeeman effects magnetic constants
下载PDF
LOCAL BIFURCATION OF STEADY ALMOST PERIODIC WATER WAVES WITH CONSTANT VORTICITY
19
作者 罗巍 殷朝阳 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1633-1644,共12页
In this paper we investigate the traveling wave solution of the two dimensional Euler equations with gravity at the free surface over a flat bed.We assume that the free surface is almost periodic in the horizontal dir... In this paper we investigate the traveling wave solution of the two dimensional Euler equations with gravity at the free surface over a flat bed.We assume that the free surface is almost periodic in the horizontal direction.Using conformal mappings,one can change the free boundary problem into a fixed boundary problem for some unknown functions with the boundary condition.By virtue of the Hilbert transform,the problem is equivalent to a quasilinear pseudodifferential equation for an almost periodic function of one variable.The bifurcation theory ensures that we can obtain an existence result.Our existence result generalizes and covers the recent result in[15].Moreover,our result implies a non-uniqueness result at the same bifurcation point. 展开更多
关键词 water waves almost periodic functions bifurcation theory constant vorticity
下载PDF
Adiabaticity Violated Not Enough: Presume Primordial Black Holes to Generate Gravitons for Cosmological Constant, as Candidate for DE Initially
20
作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期100-107,共8页
Instant preheating as given in terms of window where adiabaticity is violated is a completely inefficient form of particle production if we use Padmandabhan scalar potentials. This necessitates using a very different ... Instant preheating as given in terms of window where adiabaticity is violated is a completely inefficient form of particle production if we use Padmandabhan scalar potentials. This necessitates using a very different mechanism for early universe gravition production as an example which is to break up the initial “mass” formed about 10<sup>60</sup> times Planck mass into graviton emitting 10<sup>5</sup> gram sized micro black holes. The mechanism is to assume that we have a different condition than the usual adiabaticity idea which is connected with reheating of the universe. Hence, we will be looking at an earlier primordial black hole generation for generation of gravitons. 展开更多
关键词 Black Holes Cosmological constant Universe Gravition
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部