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超对称和环量子引力理论与粒子物理中的统一 被引量:8
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作者 张一方 《吉首大学学报(自然科学版)》 CAS 2008年第2期51-57,共7页
在超对称理论中引入与自旋无关的超旋、超同位旋和各种超对称变换,从而统一描述玻色子和费米子.同时讨论了超对称和超弦中的各种相互作用及其它方面的统一,导出了环量子引力理论的4个定量结论,提出了可能存在从超弦到宇宙弦等不同尺度... 在超对称理论中引入与自旋无关的超旋、超同位旋和各种超对称变换,从而统一描述玻色子和费米子.同时讨论了超对称和超弦中的各种相互作用及其它方面的统一,导出了环量子引力理论的4个定量结论,提出了可能存在从超弦到宇宙弦等不同尺度的泛弦. 展开更多
关键词 粒子物理 超对称 超弦 环量子引力理论 统一
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Ashtekar-Kodama Gravity as a Classical and Quantum Extension of Loop Quantum Gravity
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作者 Jan Helm 《Journal of Modern Physics》 2024年第6期864-937,共74页
This paper presents a new theory of gravity, called here Ashtekar-Kodama (AK) gravity, which is based on the Ashtekar-Kodama formulation of loop quantum gravity (LQG), yields in the limit the Einstein equations, and i... This paper presents a new theory of gravity, called here Ashtekar-Kodama (AK) gravity, which is based on the Ashtekar-Kodama formulation of loop quantum gravity (LQG), yields in the limit the Einstein equations, and in the quantum regime a full renormalizable quantum gauge field theory. The three fundamental constraints (hamiltonian, gaussian and diffeomorphism) were formulated in 3-dimensional spatial form within LQG in Ashtekar formulation using the notion of the Kodama state with positive cosmological constant Λ. We introduce a 4-dimensional covariant version of the 3-dimensional (spatial) hamiltonian, gaussian and diffeomorphism constraints of LQG. We obtain 32 partial differential equations for the 16 variables E<sub>mn</sub> (E-tensor, inverse densitized tetrad of the metric) and 16 variables A<sub>mn</sub> (A-tensor, gravitational wave tensor). We impose the boundary condition: for large distance the E-generated metric g(E) becomes the GR-metric g (normally Schwarzschild-spacetime). The theory based on these Ashtekar-Kodama (AK) equations, and called in the following Ashtekar-Kodama (AK-) gravity has the following properties. • For Λ = 0 the AK equations become Einstein equations, A-tensor is trivial (constant), and the E-generated metric g(E) is identical with the GR-metric g. • When the AK-equations are developed into a Λ-power series, the Λ-term yields a gravitational wave equation, which has only at least quadrupole wave solutions and becomes in the limit of large distance r the (normal electromagnetic) wave equation. • AK-gravity, as opposed to GR, has no singularity at the horizon: the singularity in the metric becomes a (very high) peak. • AK-gravity has a limit scale of the gravitational quantum region 39 μm, which emerges as the limit scale in the objective wave collapse theory of Gherardi-Rimini-Weber. In the quantum region, the AK-gravity becomes a quantum gauge theory (AK quantum gravity) with the Lie group extended SU(2) = ε-tensor-group(four generators) as gauge group and a corr 展开更多
关键词 quantum gravity loop quantum gravity General Relativity Gravitational Wave Gauge Field Theory Graviton Hamiltonian Constraint Gaussian Constraint Diffeomorphism Constraint
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关于宇宙暗物质主要形态之黑洞-夸克星的新证据分析 被引量:7
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作者 张海鹏 张力 +8 位作者 罗延安 范祖辉 张鹏杰 黄明球 常丽君 孟庆义 张丹参 胡扬洋 李新兵 《山西师范大学学报(自然科学版)》 2015年第2期49-54,共6页
通过分析新近证据,进一步探讨宇宙暗物质等问题,分析认为:(1)宇宙紫外辐射超出已知辐射源4倍的发现,可能就是源于我国的、2013年初预言的约在可见光附近波段的宇宙背景辐射;彭罗斯等2010年发现的CMB偏振环等新证据,较有力地支持原始夸... 通过分析新近证据,进一步探讨宇宙暗物质等问题,分析认为:(1)宇宙紫外辐射超出已知辐射源4倍的发现,可能就是源于我国的、2013年初预言的约在可见光附近波段的宇宙背景辐射;彭罗斯等2010年发现的CMB偏振环等新证据,较有力地支持原始夸克星碰撞、重组的宇宙演化及起源模型;黑洞(暗星)-夸克星可能是宇宙暗物质的主要形态,应足以解释暗物质与可见物质的比例.以上均应深入研究;(2)76个黑洞的强大磁场的发现,客观上有力地支持了星系中心超大质量黑洞等的携1/3正负电子电荷的最基本的正、负夸克构型;(3)质能守恒定律的经典物理学意义所推论的最基本夸克的空心圈环结构,为圈量子引力奠定了较坚实的粒子物理学基础;(4)结合高频引力波产生机理(激光约束核聚变等)及探测机理,应对中微子与高频引力波(引力子)进行会师研究. 展开更多
关键词 黑洞 暗星 夸克星 圈量子引力 引力波 高频 中微子 左旋 暗物质
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Is Loop Quantum Gravity a Physically Correct Quantization? 被引量:2
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作者 John R. Klauder 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第1期49-51,共3页
Dirac’s rule in which only special phase space variables should be promoted to operators in canonical quantization is applied to loop quantum gravity. For this theory, Dirac’s rule is violated, and as a result loop ... Dirac’s rule in which only special phase space variables should be promoted to operators in canonical quantization is applied to loop quantum gravity. For this theory, Dirac’s rule is violated, and as a result loop quantum gravity fails the test to be a valid quantization. Indications are included on how to create and deal with valid versions of quantum gravity. 展开更多
关键词 quantum gravity AFFINE QUANTIZATION loop quantum gravity
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A Number Theoretic Analysis of the Enthalpy, Enthalpy Energy Density, Thermodynamic Volume, and the Equation of State of a Modified White Hole, and the Implications to the Quantum Vacuum Spacetime, Matter Creation and the Planck Frequency
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作者 Michele Nardelli Amos S. Kubeka Alizera Amani 《Journal of Modern Physics》 2024年第1期1-50,共50页
In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Th... In this paper, we analyze the enthalpy, enthalpy energy density, thermodynamic volume, and the equation of state of a modified white hole. We obtain new possible mathematical connections with some sectors of Number Theory, Ramanujan Recurring Numbers, DN Constant and String Theory, that enable us to extract the quantum geometrical properties of these thermodynamic equations and the implication to the quantum vacuum spacetime geometry of our early universe as they act as the constraints to the nature of quantum gravity of the universe. 展开更多
关键词 Number Theory Ramanujan Recurring Numbers DN Constant String Theory loop quantum gravity Matter Creation Enthalpy Energy Density Thermodynamic Volume ENTHALPY
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在真相与后真相之间——量子引力理论蕴含的时空观 被引量:4
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作者 赵丹 高策 《自然辩证法通讯》 CSSCI 北大核心 2020年第1期31-36,共6页
真相时代科学的典范--广义相对论和量子力学--关于时空的观念存在冲突,在试图结合广义相对论与量子力学的量子引力理论构建中,最关键也最为困难的就是对时空的处理。文章沿着时空观念在物理学理论中的流变,着重分析了量子引力理论中所... 真相时代科学的典范--广义相对论和量子力学--关于时空的观念存在冲突,在试图结合广义相对论与量子力学的量子引力理论构建中,最关键也最为困难的就是对时空的处理。文章沿着时空观念在物理学理论中的流变,着重分析了量子引力理论中所蕴含的时空观念,揭示了量子引力理论中时空的涌现特性,探讨了其后真相的意义之所在。 展开更多
关键词 时空 量子引力 弦理论 圈量子引力
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量子真空的哲学问题 被引量:4
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作者 薛晓舟 《河南师范大学学报(哲学社会科学版)》 北大核心 2003年第5期5-9,共5页
量子场是物质的基本形态,量子场论是现代物理学的基本理论,而量子真空正是最低能量状态的量子场,这使得量子真空的研究,成为目前引人注目的自然哲学尖端课题。本文从真空是物质的一种形态、空间度量的断续性、时间度量的断续性、基本作... 量子场是物质的基本形态,量子场论是现代物理学的基本理论,而量子真空正是最低能量状态的量子场,这使得量子真空的研究,成为目前引人注目的自然哲学尖端课题。本文从真空是物质的一种形态、空间度量的断续性、时间度量的断续性、基本作用规律的量子性及统一性、物质结构基元的存在性等五个方面,讨论了当今关于量子真空的本体诠释。 展开更多
关键词 量子真空 量子场论 圈量子引力 超弦/M理论 哲学问题
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Loop quantum gravity and black hole entropy quantization 被引量:2
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作者 LI ChuanAn JIANG JiJian SU JiuQing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第8期1179-1182,共4页
Using the spin networks and the asymptotic quasinormal mode frequencies of black holes given by loop quantum gravity,the minimum horizon area gap is obtained.Then the quantum area spectrum of black holes is derived an... Using the spin networks and the asymptotic quasinormal mode frequencies of black holes given by loop quantum gravity,the minimum horizon area gap is obtained.Then the quantum area spectrum of black holes is derived and the black hole entropy is a realized quantization.The results show that the black hole entropy given by loop quantum gravity is in full accord with the Bekenstein-Hawking entropy with a suitable Immirzi. 展开更多
关键词 loop quantum gravity QUASINORMAL mode quantum area spectrum BLACK HOLE entropy QUANTIZATION
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The information entropy of a static dilaton black hole 被引量:1
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作者 LIU ChengZhou Institute of Theoretical Physics, Binzhou University, Binzhou 256600, China Department of Physics, Beijing Normal University, Beijing 100875, China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第2期113-125,共13页
In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the b... In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed. 展开更多
关键词 black hole entropy HOLOGRAPHIC principle NON-COMMUTATIVE quantum field theory event HORIZON loop quantum gravity
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Spacetime Discreteness: Shedding Light on Two of the Simplest Observations in Physics
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作者 Ahmed Isam 《Journal of Modern Physics》 2018年第7期1415-1431,共17页
Loop quantum gravity is considered to be one of the two major candidates for a theory of quantum gravity. The most appealing aspect about this theory is it predicts that spacetime is not continuous;both space and time... Loop quantum gravity is considered to be one of the two major candidates for a theory of quantum gravity. The most appealing aspect about this theory is it predicts that spacetime is not continuous;both space and time have a discrete nature. Simply, space is not infinitely divisible, but it has a granular structure, and time does not flow continuously like a smooth river. This paper demonstrates a review for two missed (unnoted) observations that support the discreteness of the spacetime. The content of this paper does not validate the specific model of quantized geometry of the spacetime which is predicted by the theory itself. Instead, it proves that time does not flow continuously. But it flows in certain, discrete steps, like a ticking of a clock, due to a simple observation which is absence of any possible value of time that can exist between the present and the future. Regarding space, it validates the spatial discreteness, and the existence of spatial granules (space quanta) due to a simple observation which is the existence of the origin position in a coordinates system. All of this is achieved by reviewing the concept of discreteness itself, and applied directly to the observations. 展开更多
关键词 quantum gravity loop quantum gravity DISCRETE TIME DISCRETE Space Emptiness PLANCK Length PLANCK TIME Infinities Problem
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Time Evolution of Horizons
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作者 Arundhati Dasgupta 《Journal of Modern Physics》 2012年第9期1289-1297,共9页
Finding the origin of Hawking radiation has been a puzzle to researchers. Using a loop quantum gravity description of a black hole slice, a density matrix is defined using coherent states for space-times with apparent... Finding the origin of Hawking radiation has been a puzzle to researchers. Using a loop quantum gravity description of a black hole slice, a density matrix is defined using coherent states for space-times with apparent horizons. Evolving the density matrix using a semi-classical Hamiltonian in the frame of an observer outside the horizon gives the origin of Hawking radiation. 展开更多
关键词 BLACK HOLE Physics quantum gravity Hawking Radiation loop quantum gravity Coherent STATES
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Counting the Microstates at the Black Hole Horizon and the Immirzi Parameter of Loop Quantum Gravity
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作者 M. Sadiq 《Journal of Applied Mathematics and Physics》 2020年第10期2055-2062,共8页
Motivated by Bekenstein’s original thought that led him to his famous area-entropy formula for a black hole and by our recent study regarding the black hole dynamics, we identify the appropriate microscopic degrees o... Motivated by Bekenstein’s original thought that led him to his famous area-entropy formula for a black hole and by our recent study regarding the black hole dynamics, we identify the appropriate microscopic degrees of freedom in loop quantum gravity that are responsible for the black hole entropy. We achieve consistent results by taking the <em>j</em> = 1/2 edges as dominant and by subjecting these edges to experience quantum fluctuations at the horizon. This also leads to a modification of the value of the Immirzi parameter in the <em>SU</em>(2) framework. 展开更多
关键词 Immirzi Parameter Spin Networks quantum gravity loop quantum gravity Isotropic Oscillator SU(2) Quasinormal Modes Black Hole
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论当代量子引力的空间时间观念 被引量:1
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作者 张敏平 薛晓舟 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2008年第1期44-48,共5页
首先讨论当代诸种量子引力,如超弦/M理论、圈量子引力等,继而研究空间时间量子涨落对量子引力理论的经验检验,最后讨论了有关量子引力时空的物理实在问题.
关键词 当代量子引力 超弦/M理论 圈量子引力 一致离散量子引力 因果集量子引力 时空量子涨落
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Ontology of Quantum Gravity
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作者 Edwin Eugene Klingman 《Journal of Modern Physics》 2023年第11期1392-1408,共17页
A theory of Quantum Gravity based on Primordial Field Theory is applied to a fundamental particle, the neutron. The result is compared to the current quantum description of the neutron bouncing in a gravitational fiel... A theory of Quantum Gravity based on Primordial Field Theory is applied to a fundamental particle, the neutron. The result is compared to the current quantum description of the neutron bouncing in a gravitational field. Our quantum gravity theory yields results in agreement with the Q-bounce experimental data, but ontologically different from quantum mechanics. The differences are summarized and imply that this experiment on a fundamental particle has the potential to radically alter the ontology of field theory. 展开更多
关键词 loop quantum gravity ONTOLOGY Neutron Bounce Primordial Field Theory Q-Bounce Neutron Flux
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量子引力的各种探索 被引量:2
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作者 吴新忠 《淮阴师范学院学报(哲学社会科学版)》 2011年第5期596-600,621,共6页
相对论和量子理论只是20世纪以来尚未完成的物理学革命的第一步,引力量子化是21世纪物理学中最大的难题。从突破量子场论中点粒子模型框架得到的超弦理论,尽管引入了新的对称性有助于统一四种基本相互作用,但量子超引力的重整化问题并... 相对论和量子理论只是20世纪以来尚未完成的物理学革命的第一步,引力量子化是21世纪物理学中最大的难题。从突破量子场论中点粒子模型框架得到的超弦理论,尽管引入了新的对称性有助于统一四种基本相互作用,但量子超引力的重整化问题并没有彻底解决,目前也没有超对称与额外维的可靠实验证据。随着宇宙暴涨证据的发现,人们被迫重新引入爱因斯坦一度放弃的宇宙学常数,弦论很难解释为何宇宙常数是非常小的负数。从引力规范理论可以延伸出圈量子引力理论,它一开始就假定时空由离散元素构成,而且时空的离散性是结合量子理论与狭义相对论的结果。而扭量理论以因果关系为基本要素,重新构造事件的时空图。目前最成功的量子引力方法结合了三个基本思想:空间是突现的,空间的最基本的描述是离散的,这些描述都以因果性为基本要素,但这些构想如何与粒子物理、量子场论结合仍然是个未解之谜。 展开更多
关键词 超弦 圈量子引力 扭量理论
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圈量子宇宙学的新进展 被引量:1
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作者 马永革 《中国科学:物理学、力学、天文学》 CSCD 北大核心 2011年第12期1409-1413,共5页
圈量子宇宙学在国际引力和宇宙学界日益成为一个热门的研究领域.本文将介绍圈量子引力理论的基本想法及其对称约化模型-圈量子宇宙学的基本结构与最新进展.新进展侧重于圈量子宇宙学的动力学构造及其有效理论的研究.
关键词 圈量子引力 圈量子宇宙学 联络 哈密顿约束
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Immirzi parameter and quasinormal modes in four and higher spacetime dimensions
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作者 Xiang-Dong Zhang 《Frontiers of physics》 SCIE CSCD 2016年第4期133-136,共4页
There is a one-parameter quantization ambiguity in loop quantum gravity, which is called the Immirzi parameter. In this paper, we fix this free parameter by considering the quasinormal mode spectrum of black holes in ... There is a one-parameter quantization ambiguity in loop quantum gravity, which is called the Immirzi parameter. In this paper, we fix this free parameter by considering the quasinormal mode spectrum of black holes in four and higher spacetime dimensions. As a consequence, our result is consistent with the Bekenstein-Hawking entropy of a black hole. Moreover, we also give a possible quantum gravity explanation of the universal In 3 behavior of the quasinormal mode spectrum. 展开更多
关键词 Immirzi parameter quasinormal mode loop quantum gravity
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Entropy of nonrotating isolated horizons in Lovelock theory from loop quantum gravity
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作者 王晶波 黄超光 李林 《Chinese Physics C》 SCIE CAS CSCD 2016年第8期33-36,共4页
In this paper, the BF theory method is applied to the nonrotating isolated horizons in Lovelock theory. The final entropy matches the Wald entropy formula for this theory. We also confirm the conclusion obtained by Bo... In this paper, the BF theory method is applied to the nonrotating isolated horizons in Lovelock theory. The final entropy matches the Wald entropy formula for this theory. We also confirm the conclusion obtained by Bodendorfer et al. that the entropy is related to the flux operator rather than the area operator in general diffeomorphic-invariant theory. 展开更多
关键词 loop quantum gravity entropy of isolated horizons Lovelock theory
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Consistency check on the fundamental and alternative flux operators in loop quantum gravity
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作者 Jinsong Yang Yongge Ma 《Chinese Physics C》 SCIE CAS CSCD 2019年第10期50-60,共11页
There are different constructions of the flux of triad in loop quantum gravity, namely the fundamental and alternative flux operators. In parallel to the consistency check on the two versions of operator by the algebr... There are different constructions of the flux of triad in loop quantum gravity, namely the fundamental and alternative flux operators. In parallel to the consistency check on the two versions of operator by the algebraic calculus in the literature, we check their consistency by the graphical calculus. Our calculation based on the original Brink graphical method is obviously simpler than the algebraic calculation. It turns out that our consistency check fixes the regulating factor κreg of the Ashtekar-Lewandowski volume operator as 1/2, which corrects its previous value in the literature. 展开更多
关键词 loop quantum gravity FLUX operator GRAPHICAL CALCULUS
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Entanglement in simple spin networks with a boundary
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作者 Yi Ling Meng-He Wu Yikang Xiao 《Chinese Physics C》 SCIE CAS CSCD 2019年第1期56-64,共9页
We investigate the bipartite entanglement for the boundary states in a simple type of spin networks with dangling edges, in which the two complementary parts are linked by two or more edges. Firstly, the spin entangle... We investigate the bipartite entanglement for the boundary states in a simple type of spin networks with dangling edges, in which the two complementary parts are linked by two or more edges. Firstly, the spin entanglement is considered in the absence of the intertwiner entanglement. By virtue of numerical simulations, we find that the entanglement entropy usually depends on the group elements. More importantly, when the intertwiner entanglement is taken into account, we find that it is in general impossible to separate the total entanglement entropy into the contribution from spins on edges and the contribution from intertwiners at vertices. These situations are in contrast to the case when the two vertices are linked by a single edge. 展开更多
关键词 ENTANGLEMENT SPIN network loop quantum gravity
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