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91.
92.
《Quaestiones Mathematicae》2013,36(3):290-304
Abstract A categorical notion of interior operator is used in topology to define connectedness and disconnectedness with respect to an interior operator. A commutative diagram of Galois connections is used to show a relationship between these notions and Arhangelskii and Wiegandt's notions of connectedness and disconnectedness with respect to a subclass of topological spaces. Examples are included. 相似文献
93.
94.
《Journal of Nonlinear Mathematical Physics》2013,20(2):236-246
In this article, we focus on left-invariant pseudo-Einstein metrics on Lie groups. To begin with, we give some examples of pseudo-Einstein metrics on Lie groups. Also we calculate the Levi-civita connection, and then Ricci tensor associated with left-invariant pseudo-Riemannian metrics on the unimodular Lie groups of dimension three. Furthermore, we show that the left-invariant pseudo-Einstein metric on SL(2) is unique up to a constant. At last, we study the left-invariant pseudo-Riemannian metrics on compact Lie groups and classify the pseudo-Einstein metrics on the low-dimensional compact Lie groups. 相似文献
95.
WANG Dian-Fu ZHONG Hai-Yang 《理论物理通讯》2008,50(9):703-706
Generalized Yang-Mills theory has a covariant derivative which contains both vector and pseudoscalar gauge bosons. Based on this theory, we construct a U(4) strong interaction model. By using this U(4) generalized Yang-Mills model, we obtain that mesons can be realized as the colorless pseudoscalar gauge bosons. We also obtain a gauge potential solution which can be used to explain the asymptotic behavior and color confinement. 相似文献
96.
WANG Dian-Pu 《理论物理通讯》2008,50(12):1387-1390
In terms of the Nambu-Jona-Lasinio mechanism, dynamical breaking of gauge symmetry for the maximally generalized Vang-Mills model is investigated. The gauge symmetry behavior at finite temperature is also investigated and it is shown that the gauge symmetry broken dynamically at zero temperature can be restored at finite temperatures. 相似文献
97.
98.
99.
To any (0, 2)-tensor field on the tangent bundle of a Riemannian manifold, we associate a global matrix function. Based on this fact, natural tensor fields are defined and characterized, essentially by means of well-known algebraic results. In the symmetric case, this classification coincides with the one given by Kowalski–Sekizawa; in the skew-symmetric one, it does with that obtained by Janyka. 相似文献
100.
Qikeng Lu 《中国科学A辑(英文版)》1998,41(12):1248-1254
In the complex Grassmann manifold ℱ(m,n), the space of complexn-planes passes through the origin of Cm+n; the local coordinate of the space can be arranged into anm ×n matrixZ. It is proved that
is a U(m)-connection of ℱ(m,n) and its curvature form
satisfies the Yang-Mills equation. Moreover,
is an (Sum)-connection and its curvature form
satisfies the Yang-Mills equation.
Project partially supported by the National Natural Science Foundation of China (Grant No. 19631010) and Fundamental Research
Bureau of CAS. 相似文献