首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 234 毫秒
1.
从无挠嘉当几何的观点出发讨论了非阿贝尔规范势的分解.借助γ-矩阵和洛仑兹群生成元的对易关系,得到相应的“同位旋空间”的规范势的表达式.  相似文献   

2.
罗晓丽  高建华 《物理学报》2023,(11):128-136
非阿贝尔规范场是构成标准模型的基本单元,非阿贝尔手征动理学理论是描述标准模型在非平衡体系下手征费米子输运的重要理论工具.在前期工作中,我们将非阿贝尔手征动理学方程分解为色空间中的色单态和色多重态等不可约表示形式,这种分解方式可以让手征动理学方程在色空间的规范变换下具有更简单的变换性质.然而,这种分解方式在微观描述色自由度的输运方面可能并不直观和方便.为了描述色自由度具体输运和演化过程,本文把前期得到的非阿贝尔手征动理学方程在嘉当韦尔基下进行展开.本文中通过协变梯度展开的方法将非阿贝尔手征动理学方程展开到1阶,在嘉当韦尔基下将规范场进行展开,分布函数分解为对角元素部分和非对角元素部分.结果显示0阶非对角元素分布函数可以诱导出1阶对角元素分布函数贡献,0阶对角元素分布函数也可以诱导出1阶非对角元素分布函数的贡献.非对角元素分布函数之间以及非对角元素与对角元素之间一般都是耦合在一起,但当规范场只存在对角元素时,非对角元素与对角元素解耦.  相似文献   

3.
基于联络分解变量的紫外/红外分离, 提出杨-米尔斯理论真空的强耦合极限表现为一个经典场论意义下色空间的黑洞. 基于此想法, 证明在强耦合杨-米尔斯理论中存在对偶超导体解. 在量子水平下, 强耦合理论的非微扰真空可由磁荷的多粒子体系构成, 而理论的经典平均给出对偶阿贝尔-黑格斯模型. 该模型预言了与最近的格点模拟相一致的结果: 理论真空位于第一类与第二类超导体边界. 进一步通过求解对偶阿贝尔-黑格斯模型讨论了色电场的对偶迈斯纳效应.  相似文献   

4.
本文将定域规范不变的平均场方法由分立的阿贝尔群情况推广至非阿贝尔连续群情况, 计算了SU(2)Yang-Mills场和Higgs场耦合系统的相图.  相似文献   

5.
 过去几十年中,场论研究取得了重大进展.毫无疑问,最重要的部分与我们对于规范对称性、规范群的性质的深入了解及其应用密切相关.相互作用的规范不变性作为试探建立各种相互作用动力学理论的指导原理取得了极大的成功.除掉早已知道的电磁作用的阿贝尔对称性以外,应用非阿贝尔规范对称性理论建立了弱作用及电磁作用的统一理论及强作用的量子色动力学.  相似文献   

6.
邱荣 《中国物理 C》1993,17(3):227-240
导出了与"阿贝尔手征群陪集空间纯规范场的生成泛函路径积分测度和有效作用量联合起来在手征群变换下具有不变性"相应的恒等式.利用此恒等式建造了重整化方程,并由方程的解将阿贝尔手征群陪集纯规范场理论重整化.  相似文献   

7.
单极是规范场的一个内禀拓扑因素,而且单极的拓扑结构已足决定它的运动规律,这无论在阿贝尔或非阿贝尔场都如是。本文对规范场中单极子的基本概念作一个简单的介绍,并稍为涉及孤子单极,和单极在物理世界的可能存在问题。  相似文献   

8.
单极是规范场的一个内禀拓扑因素,而且单极的拓扑结构已足决定它的运动规律,这无论在阿贝尔或非阿贝尔场都如是。本文对规范场中单极子的基本概念作一个简单的介绍,并稍为涉及孤子单极,和单极在物理世界的可能存在问题。  相似文献   

9.
张肇西 《物理》2000,29(2):76-77
因30年前解决了非阿贝尔规范场重整化的理论问题,特霍夫特和威特曼两位教授获得了1999年诺贝尔物理学奖。解决非阿贝尔规范场重整化的理化问题需要独特的技巧,而且非常有用。他们关于非阿贝尔规范场重整化所取得的成就,现已被广泛用于粒子物理的理论精确计算中,并且通过实验和计算结果精确地比较,已证实了它的正确性。  相似文献   

10.
孙昌璞 《中国物理 C》1990,14(7):604-613
在对称性变化的简并情况下,本文建议了一种逐级求解具有缓变参数的量子力学体系演化的解析方法——简并情况下的高级绝热近似方法.本文不仅利用其零级近似证明了简并情况的量子绝热定理,并讨论了非阿贝尔诱导规范结构,而且指出了高级近似导致的非绝热效应.采用本文的方法,以核四极共振问题为例,详细地分析了非阿贝尔诱导规范结构在绝热和非绝热实验过程中的可观察效应.  相似文献   

11.
使用几何代数方法,研究了n维紧致黎曼流形上SO(n)规范势(自旋联络)的一般分解理论,建立了SO(n)规范场用球丛上单位矢量场n分解的一般表达式.由此,分别得到了U(1)规范场和U(2)规范场用单位矢量场n分解的一般形式.  相似文献   

12.
规范势可分解理论及其应用   总被引:1,自引:0,他引:1  
对近几年用几何代数方法建立的规范场可分解理论进行了详细的评述 ,并给出了应用它研究欧拉示性数的新结果 .简述了一些应用领域.从目前国际研究的进展来看 ,规范势可分解理论也将为研究规范场静态解和夸克禁闭提供新的途径. The recent study of decomposition of gauge fields by means of methods of the geometric algebra was reviewed in detail. The new results in the study of the Euler characteristic by using the decomposition of gauge fields were described. On the other hand, some recent application fields of the decomposition of gauge fields and topological current theory were introduced. The new developments of the investigation in the area have also shown that the decomposition of gauge fields will provide...  相似文献   

13.
The prevailing theoretical quark and gluon momentum, orbital angular momentum and spin operators, satisfy either gauge invariance or the corresponding canonical commutation relation, but one never has these operators which satisfy both except the quark spin. The conflicts between gauge invariance and the canonical quantization requirement of these operators are discussed. A new set of quark and gluon momentum, orbital angular momentum and spin operators, which satisfy both gauge invariance and canonical momentum and angular momentum commutation relation, are proposed. To achieve such a proper decomposition the key point is to separate the gauge field into the pure gauge and the gauge covariant parts. The same conflicts also exist in QED and quantum mechanics, and have been solved in the same manner. The impacts of this new decomposition to the nucleon internal structure are discussed.  相似文献   

14.
It is unavoidable to deal with the quark and gluon momentum and angular momentum contributions to the nucleon momentum and spin in the study of nucleon internal structure. However we never have the quark and gluon momentum, orbital angular momentum and gluon spin operators which satisfy both the gauge invariance and the canonical momentum and angular momentum commutation relation. The conflicts between the gauge invariance and canonical quantization requirement of these operators are discussed. A new set of quark and gluon momentum, orbital angular momentum and spin operators, which satisfy both the gauge invariance and canonical momentum and angular momentum commutation relation, are proposed. The key point to achieve such a proper decomposition is to separate the gauge field into the pure gauge and the gauge covariant parts. The same conflicts also exist in QED and quantum mechanics and have been solved in the same manner. The impacts of this new decomposition to the nucleon internal structure are discussed.  相似文献   

15.
Girish S Setlur 《Pramana》2004,62(1):101-114
It is shown that gauge theories are most naturally studied via a polar decomposition of the field variable. Gauge transformations may be viewed as those that leave the density invariant but change the phase variable by additive amounts. The path integral approach is used to compute the partition function. When gauge fields are included, the constraint brought about by gauge invariance simply means an appropriate linear combination of the gradients of the phase variable and the gauge field is invariant. No gauge fixing is needed in this approach that is closest to the spirit of the gauge principle. We derive an exact formula for the condensate fraction and in case it is zero, an exact formula for the anomalous exponent. We also derive a formula for the vortex strength which involves computing radiation corrections.  相似文献   

16.
We investigate the decomposition of noncommutative gauge potential Âi, and find that it has inner structure, namely, Âi can be decomposed in two parts, hat{b}i and âi, where hat{b}i satisfies gauge transformations while âi satisfies adjoint transformations, so dose the Seiberg-Witten mapping of noncommutative U(1) gauge potential. By means of Seiberg-Witten mapping, we construct a mapping of unit vector field between noncommutative space and ordinary space, and find the noncommutative U(1) gauge potential and its gauge field tensor can be expressed in terms of the unit vector field. When the unit vector field has no singularity point, noncommutative gauge potential and gauge field tensor will equal ordinary gauge potential and gauge field tensor  相似文献   

17.
We study initial value problems of the Chern–Simons–Dirac equations. With the Lorentz gauge condition they are formulated in the second-order hyperbolic equations. Under the Coulomb gauge condition Dirac equation is coupled with the elliptic equations which show some smoothing properties of the gauge field. With the temporal gauge condition divergence-curl decomposition and elliptic estimates will be used. JSPS Research Follow supported by JSPS Grant-in-Aid  相似文献   

18.
The decomposition of Feynman integrals with massless propagators into hard and soft contributions is systematically effected in renormalized field theory. It is shown that the decomposition leads to an elegant method of renormalizing massless field theories. Ultraviolet and infrared finite composite fields (normal products) are defined and renormalized field equations are derived. Exploiting a gauge principle, scalar ghosts arising in the hard-soft decomposition are eliminated and a renormalization group equation is derived to describe the effects of changes in the mass scale.  相似文献   

19.
In this paper, a novel decomposition expression for the U(1) gauge field in liquid crystals (LCs) is derived. Using this decomposition expression and the b-mapping topological current theory, we investigate the topological structure of the vortex lines in LCs in detail. A topological invariant, i.e., the Chern-Simons (CS) action for the knotted vortex lines is presented, and the CS action is shown to be the total sum of all the self-linking and linking numbers of the knot family. Moreover, it is pointed out that the CS action is preserved in the branch processes of the knotted vortex lines.  相似文献   

20.
Based on the decomposition theory of the U(1) gauge potential, the inner structure of the statistical gauge potential in the Chern-Simons-Ginzburg-Landau (CSGL) theory is studied. We give a new creation mechanism of the statistical gauge potential. Furthermore, making use of the φ-mapping topological current theory, we obtain the precise topological expression of the statistical magnetic field, which takes the topological information of the vortices.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号