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SOLUTIONS TO DISCRETE MULTIPARAMETER PERIODIC BOUNDARY VALUE PROBLEMS INVOLVING THE p-LAPLACIAN VIA CRITICAL POINT THEORY 被引量:8
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作者 高承华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1225-1236,共12页
In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value ... In this paper, we consider the existence of three nontrivial solutions for a discrete non-linear multiparameter periodic problem involving the p-Laplacian. By using the similar method for the Dirichlet boundary value problems in [C. Bonanno and P. Candito, Appl. Anal., 88(4) (2009), pp. 605-616], we construct two new strong maximum principles and obtain that the boundary value problem has three positive solutions for λ and μ in some suitable intervals. The approaches we use are the critical point theory. 展开更多
关键词 discrete periodic boundary value problem P-LAPLACIAN MULTIPARAMETER three solutions critical point theory
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Ecological suitability evaluation for urban growth boundary in red soil hilly areas based on fuzzy theory 被引量:6
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作者 焦胜 高青 +5 位作者 魏春雨 刘贝 李晓东 曾光明 袁中兴 梁婕 《Journal of Central South University》 SCIE EI CAS 2012年第5期1364-1369,共6页
The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aimin... The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future. 展开更多
关键词 land ecological suitability evaluation fuzzy theory urban growth boundary (UGB) GIS MATLAB
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Domain boundaries in silicene:Density functional theory calculations on electronic properties 被引量:1
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作者 肖红君 张礼智 +1 位作者 杜世萱 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期116-119,共4页
By using density functional theory(DFT)-based first-principles calculations, the structural stability and electronic properties for two kinds of silicene domain boundaries, forming along armchair edge and zigzag edge,... By using density functional theory(DFT)-based first-principles calculations, the structural stability and electronic properties for two kinds of silicene domain boundaries, forming along armchair edge and zigzag edge, have been investigated. The results indicate that a linkage of tetragonal and octagonal rings(4|8) appears along the armchair edge, while a linkage of paired pentagonal and octagonal rings(5|5|8) appears along the zigzag edge. Different from graphene, the buckling properties of silicene lead to two mirror symmetrical edges of silicene line-defect. The formation energies indicate that the 5|5|8 domain boundary is more stable than the 4|8 domain boundary. Similar to graphene, the calculated electronic properties show that the 5|5|8 domain boundaries exhibit metallic properties and the 4|8 domain boundaries are half-metal.Both domain boundaries create the perfect one-dimensional(1D) metallic wires. Due to the metallic properties, these two kinds of nanowires can be used to build the silicene-based devices. 展开更多
关键词 domain boundaries SILICENE line defect density functional theory
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EQUIVALENT BOUNDARY INTEGRAL EQUATIONS WITH INDIRECT UNKNOWNS FOR THIN ELASTIC PLATE BENDING THEORY 被引量:1
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作者 张耀明 孙焕纯 杨家新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第11期1246-1255,共10页
Equivalent Boundary Integral Equations (EBIE) with indirect unknowns for thin elastic plate bending theory, which is equivalent to the original boundary value problem, is established rigorously by mathematical techniq... Equivalent Boundary Integral Equations (EBIE) with indirect unknowns for thin elastic plate bending theory, which is equivalent to the original boundary value problem, is established rigorously by mathematical technique of non-analytic continuation and is fully proved by means of the variational principle. The previous three kinds of boundary integral equations with indirect unknowns are discussed thoroughly and it is shown that all previous results are not EBIE. 展开更多
关键词 thin plate bending theory boundary element method equivalent boundary integral equations?
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Boundary Hamiltonian Theory for Gapped Topological Orders 被引量:2
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作者 胡愈挺 万义顿 吴咏时 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期207-211,共5页
We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian i... We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian in our approach yields a topologically protected, gapped energy spectrum, with the corresponding wave functions robust under topology-preserving transformations of the lattice of the system. We explicitly present the wavefunctions of the ground states and boundary elementary excitations. The creation and hopping operators of boundary quasi-particles are constructed. It is found that given a bulk topological order, the gapped boundary conditions are classified by Frobenius algebras in its input data. Emergent topological properties of the ground states and boundary excitations are characterized by (bi-) modules over Frobenius algebras. 展开更多
关键词 boundary Hamiltonian theory for Gapped Topological Orders
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Perturbation Theory Combined with Boundary Element Method for Analysis of Gear Contact Problems
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作者 罗立风 常山 陈谌闻 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第3期48-52,共5页
This paper combines the perturbation theory with the boundary element methodfor contact problems of three-dimensional elasticity mechanism to analyse the effect oferrors on the shape of the contact area and pressure d... This paper combines the perturbation theory with the boundary element methodfor contact problems of three-dimensional elasticity mechanism to analyse the effect oferrors on the shape of the contact area and pressure distribution in gear drive through theperturbation of a cubic order geometry,there by greatly bringing down both computationwork volume and cost and providing a powerful tool for engineering study on the effectof errors on structural strength. 展开更多
关键词 PERTURBATION theory boundary ELEMENT method error GEAR
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Linear stability theory with the equivalent spanwise wavenumber correction in 3D boundary layers
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作者 Runjie SONG Shaolong ZHANG Jianxin LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第3期407-420,共14页
The prediction on small disturbance propagation in complex three-dimensional(3D) boundary layers is of great significance in transition prediction methodology, especially in the aircraft design. In this paper, the lin... The prediction on small disturbance propagation in complex three-dimensional(3D) boundary layers is of great significance in transition prediction methodology, especially in the aircraft design. In this paper, the linear stability theory(LST) with the equivalent spanwise wavenumber correction(ESWC) is proposed in order to accurately predict the linear evolution of a disturbance in a kind of boundary layer flow with a vital variation in the spanwise direction. The LST with the ESWC takes not only the scale of the mean flow with the significant variation but also the wavenumber evolution of the disturbance itself. Compared with the conventional LST, the results obtained by the new method are in excellent agreement with those of the numerical simulations. The LST with the ESWC is an effective method on the prediction of the disturbance evolution in 3D boundary layers, which improves the prediction of the LST in the applications to complex 3D boundary layers greatly. 展开更多
关键词 three-dimensional(3D)boundary layer prediction of DISTURBANCE propagation EQUIVALENT spanwise WAVENUMBER LINEAR stability theory(LST) numerical simulation
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Study on the Existence of Sign-Changing Solutions of Case Theory Based a Class of Differential Equations Boundary-Value Problems 被引量:1
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作者 Hongwei Ji 《Advances in Pure Mathematics》 2017年第12期686-691,共6页
By using the fixed point theorem under the case structure, we study the existence of sign-changing solutions of A class of second-order differential equations three-point boundary-value problems, and a positive soluti... By using the fixed point theorem under the case structure, we study the existence of sign-changing solutions of A class of second-order differential equations three-point boundary-value problems, and a positive solution and a negative solution are obtained respectively, so as to popularize and improve some results that have been known. 展开更多
关键词 Case theory boundary-Value PROBLEMS Fixed POINT THEOREM Sign-Changing SOLUTIONS
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SOLUTION TO A PARAMETRIC EQUATION WITH GENERALIZED BOUNDARY CONDITION IN TRANSPORT THEORY
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作者 王胜华 姚爱翔 《Acta Mathematica Scientia》 SCIE CSCD 1992年第4期435-442,共8页
This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has ... This paper deals with the solution of a parametric equation with generalized boundary condiiton in transport theory. It gives the distribution of parameter (so called delta-eigenvalue [1]) with which the equation has non-zero solution. A necessary and sufficient condition for the existence of; he control critical eigenvalue delta0 is established. 展开更多
关键词 SOLUTION TO A PARAMETRIC EQUATION WITH GENERALIZED boundary CONDITION IN TRANSPORT theory Za
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Using Foucaults theory to analyze the relationship between people,organizations,space,power and boundary
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作者 Shuaijin Qi 《Journal of World Architecture》 2021年第5期1-4,共4页
This article will use Foucaulfs theory to critically consider the relationship between power,people,space and society at the boundary where different powers conflict with each other.Through the analysis of the project... This article will use Foucaulfs theory to critically consider the relationship between power,people,space and society at the boundary where different powers conflict with each other.Through the analysis of the project“Decolonizing Al Nada,”this article will discuss how relations with those with power and social mentality are reframed at the border through the reconstruction of architecture and space. 展开更多
关键词 FoucaultJs theory POWER boundary RECONSTRUCTION
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THE INTERIOR TRANSMISSION EIGENVALUE PROBLEM FOR AN ANISOTROPIC MEDIUM BY A PARTIALLY COATED BOUNDARY
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作者 向建立 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期339-354,共16页
We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and... We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission conditions.Using the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of eigenvalues.Then we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is applied.In the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method. 展开更多
关键词 interior transmission eigenvalue anisotropic medium partially coated boundary the analytic Fredholm theory T-coercive method
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Least Square Finite Element Model for Analysis of Multilayered Composite Plates under Arbitrary Boundary Conditions
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作者 Christian Mathew Yao Fu 《World Journal of Engineering and Technology》 2024年第1期40-64,共25页
Laminated composites are widely used in many engineering industries such as aircraft, spacecraft, boat hulls, racing car bodies, and storage tanks. We analyze the 3D deformations of a multilayered, linear elastic, ani... Laminated composites are widely used in many engineering industries such as aircraft, spacecraft, boat hulls, racing car bodies, and storage tanks. We analyze the 3D deformations of a multilayered, linear elastic, anisotropic rectangular plate subjected to arbitrary boundary conditions on one edge and simply supported on other edge. The rectangular laminate consists of anisotropic and homogeneous laminae of arbitrary thicknesses. This study presents the elastic analysis of laminated composite plates subjected to sinusoidal mechanical loading under arbitrary boundary conditions. Least square finite element solutions for displacements and stresses are investigated using a mathematical model, called a state-space model, which allows us to simultaneously solve for these field variables in the composite structure’s domain and ensure that continuity conditions are satisfied at layer interfaces. The governing equations are derived from this model using a numerical technique called the least-squares finite element method (LSFEM). These LSFEMs seek to minimize the squares of the governing equations and the associated side conditions residuals over the computational domain. The model is comprised of layerwise variables such as displacements, out-of-plane stresses, and in- plane strains, treated as independent variables. Numerical results are presented to demonstrate the response of the laminated composite plates under various arbitrary boundary conditions using LSFEM and compared with the 3D elasticity solution available in the literature. 展开更多
关键词 Multilayered Composite and Sandwich Plate Transverse Stress Continuity Condition Arbitrary boundary Condition Layerwise theory Least-Squares Formulation
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The Bipolar Theory of the Field-Effect Transistor:X.The Fundamental Physics and Theory(All Device Structures)
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作者 薩支唐 揭斌斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期613-619,共7页
This paper describes the foundation underlying the device physics and theory of the semiconductor field effect transistor which is applicable to any devices with two carrier species in an electric field. The importanc... This paper describes the foundation underlying the device physics and theory of the semiconductor field effect transistor which is applicable to any devices with two carrier species in an electric field. The importance of the boundary conditions on the device current-voltage characteristics is discussed. An illustration is given of the transfer DCIV characteristics computed for two boundary conditions,one on electrical potential,giving much higher drift-limited parabolic current through the intrinsic transistor, and the other on the electrochemical potentials, giving much lower injection-over-thebarrier diffusion-limited current with ideal 60mV per decade exponential subthreshold roll-off, simulating electron and hole contacts. The two-MOS-gates on thin pure-body silicon field-effect transistor is used as examples 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor electric potential electrochemical potential boundary conditions
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The Bipolar Field-Effect Transistor:V.Bipolar Electrochemical Current Theory(Two-MOS-Gates on Thin-Base)
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作者 揭斌斌 薩支唐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期620-627,共8页
This paper reports the intrinsic-structure DC characteristics computed from the analytical electrochemical current theory of the bipolar field-effect transistor (BiFET) with two identical MOS gates on nanometer-thic... This paper reports the intrinsic-structure DC characteristics computed from the analytical electrochemical current theory of the bipolar field-effect transistor (BiFET) with two identical MOS gates on nanometer-thick pure-base of silicon with no generation-recombination-trapping. Numerical solutions are rapidly obtained for the three potential variables,electrostatic and electron and hole electrochemical potentials,to give the electron and hole surface and volume channel currents,using our cross-link two-route or zig-zag one-route recursive iteration algorithms. Boundary conditions on the three potentials dominantly affect the intrinsic-structure DC characteristics,illustrated by examples covering 20-decades of current (10-22 to 10-2 A/Square at 400cm^2/(V · s) mobility for 1.5nm gate-oxide, and 30nm-thick pure-base). Aside from the domination of carrier space-charge-limited drift current in the strong surface channels,observed in the theory is also the classical drift current saturation due to physical pinch-off of an impure-base volume channel depicted by the 1952 Shockley junction-gate field-effect transistor theory,and its extension to complete cut-off of the pure-base volume channel,due to vanishing carrier screening by the few electron and hole carriers in the pure-base,with Debye length (25mm) much larger than device dimension (25nm). 展开更多
关键词 bipolar field-effect transistor theory recursive iteration electron and hole electrochemical potentials electric potential boundary conditions
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THE BOUNDARY INTEGRAL METHOD FOR THE HELMHOLTZ EQUATION WITH CRACKS INSIDE A BOUNDED DOMAIN 被引量:3
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作者 郭军 范丽丽 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期539-551,共13页
We consider a kind of scattering problem by a crack F that is buried in a bounded domain D, and we put a point source inside the domain D. This leads to a mixed boundary value problem to the Helmholtz equation in the ... We consider a kind of scattering problem by a crack F that is buried in a bounded domain D, and we put a point source inside the domain D. This leads to a mixed boundary value problem to the Helmholtz equation in the domain D with a crack Г. Both sides of the crack F are given Dirichlet-impedance boundary conditions, and different boundary condition (Dirichlet, Neumann or Impedance boundary condition) is set on the boundary of D. Applying potential theory, the problem can be reformulated as a system of boundary integral equations. We establish the existence and uniqueness of the solution to the system by using the Fredholm theory. 展开更多
关键词 boundary integral equation Helmholtz equation Fredholm theory
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EXISTENCE OF SOLUTIONS FOR HIGHER ORDER MULTI-POINT BOUNDARY VALUE PROBLEM AT RESONANCE 被引量:3
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作者 林晓洁 杜增吉 葛渭高 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第5期705-711,共7页
Using the theory of coincidence degree, a class of higher order multi-point boundary value problem for ordinary differential equations are studied. Under the boundary conditions satisfying the resonance case, some new... Using the theory of coincidence degree, a class of higher order multi-point boundary value problem for ordinary differential equations are studied. Under the boundary conditions satisfying the resonance case, some new existence results are obtained by supposing some conditions to the nonlinear term and applying a priori estimates. 展开更多
关键词 boundary value problem RESONANCE coincidence degree theory
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Existence Results of Third Order Multi-Point Boundary Value Problem at Resonance 被引量:3
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作者 杜增吉 白占兵 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期449-452,共4页
A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0,... A kind of third order multi-point boundary value problems, x'''( ι) = f( t, x ( t ), x" ( t ), x''' ( t ) ) + m 2 e(t),t∈(0, 1),x(0)=ax(ξ),x'(0)-0,x(l)= ^m2∑j=1 βjx(ηj), fεC[0, 1]×R^3, e(t)∈L^1[0, 1],a≥0, is considered, all theβj's have not the same sign, 0〈ξ〈 l, 0〈η1〈 η2〈… 〈ηm.2〈 1. By using the coincidence degree theory, some existence theorems for the problems at resonance are obtained. 展开更多
关键词 multi-point boundary value problem RESONANCE coincidence degree theory
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Existence of Sign-changing Solution for Three-point Boundary Value Problems 被引量:4
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作者 LI Chun-yan SU Ya-juan 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期458-466,共9页
In this paper, by using the fixed-point index theory, we study the existence of sign-changing solution of some three-point boundary value problems {y ''(t) + f(y) = 0, t ∈ [0, 1], y' (0) = 0, y(1) = αy(... In this paper, by using the fixed-point index theory, we study the existence of sign-changing solution of some three-point boundary value problems {y ''(t) + f(y) = 0, t ∈ [0, 1], y' (0) = 0, y(1) = αy(η), where 0 < α < 1, 0 < η < 1, f : R → R is continuous, strictly increasing and f(0) = 0. 展开更多
关键词 three-point boundary value problem sign-changing solution the fixed-point index theory
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A numerical investigation of bubble dynamics based on the potential-flow theory 被引量:4
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作者 YAO Xiong-liang ZHANG A-man 《Journal of Marine Science and Application》 2006年第4期14-21,共8页
In this paper, the flow field is assumed to be inviscid, irrotational and incompressible, triangular elements are adopted to discretize the boundary of flow field, the boundary integral method is used to solve the flo... In this paper, the flow field is assumed to be inviscid, irrotational and incompressible, triangular elements are adopted to discretize the boundary of flow field, the boundary integral method is used to solve the flow field and the Mixed-Eulerian-Lagrangian method is applied to simulate the evolution of bubble. Three-dimensional smoothing method is used to smooth the bubble surface and the velocity potential to make the computing process more accurate and stable. In the analysis process, three-dimensional model simulates the dynamics of a bubble in the free field, gravitational field and near the rigid wall respectively, and the calculated results coincide well with the exact results and experimental data, which show that the algorithm and 3D model in this paper are of high accuracy. Calculation process indicates that bubble takes on strong non-linear under the combine effect of gravity and rigid wall. 展开更多
关键词 BUBBLE potential-flow theory boundary integral JET rigid wall THREE-DIMENSIONAL
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Entanglement of E8E8 Exceptional Lie Symmetry Group Dark Energy, Einstein’s Maximal Total Energy and the Hartle-Hawking No Boundary Proposal as the Explanation for Dark Energy 被引量:7
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 2014年第2期74-77,共4页
The present note is concerned with two connected and highly important fundamental questions of physics and cosmology, namely if E8E8 Lie symmetry group describes the universe and where cosmic dark energy comes from. F... The present note is concerned with two connected and highly important fundamental questions of physics and cosmology, namely if E8E8 Lie symmetry group describes the universe and where cosmic dark energy comes from. Furthermore, we reason following Wheeler, Hartle and Hawking that since the boundary of a boundary is an empty set which models the quantum wave of the cosmos, then it follows that dark energy is a fundamental physical phenomenon associated with the boundary of the holographic boundary. This leads directly to a clopen universe which is its own Penrose tiling-like multiverse with energy density in full agreement with COBE, WMAP and Type 1a supernova cosmic measurements. 展开更多
关键词 E8 Exceptional Lie Symmetry GROUP Dark Energy Einstein’s Relativity E-INFINITY theory Wheeler boundary of a boundary Hartle-Hawking NO boundary PROPOSAL Penrose Tiling Multiverse
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