There are two kinds of definitions of perturbation of physical quantities in the framework of general relativity: one is direct, the other is geometrical. Correspondingly, there are two types of gauge transformation ...There are two kinds of definitions of perturbation of physical quantities in the framework of general relativity: one is direct, the other is geometrical. Correspondingly, there are two types of gauge transformation related with these two definitions. The passive approach is based on the property of general covariance, and the active one is through the action of Lie-derivative. Although under a proper coordinate choice, the two approaches seem to agree with each other, they are different in nature. The geometrical definition of relativistic perturbation and the active approach for gauge transformation are more rigorous in mathematics and less confusing in physical explanation. The direct definition, however, seems to be plagued with difficulties in physical meaning, and the passive approach is more awkward to use, especially for high-order gauge transformations.展开更多
In this paper we mainly study derivation algebras of n-Lie algebras. We give the detailed structural description of derivation algebras of n + 1 dimensional n-Lie algebras over the real field.
In this paper,we give the notion of derivations of Lie 2-algebras using explicit formulas,and construct the associated derivation Lie 3-algebra.We prove that isomorphism classes of non-abelian extensions of Lie 2-alge...In this paper,we give the notion of derivations of Lie 2-algebras using explicit formulas,and construct the associated derivation Lie 3-algebra.We prove that isomorphism classes of non-abelian extensions of Lie 2-algebras are classified by equivalence classes of morphisms from a Lie 2-algebra to a derivation Lie 3-algebra.展开更多
基金supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,the Ministry of Educationthe Chinese Academy of Sciences under Grant No.KJCX3-SYW-N2
文摘There are two kinds of definitions of perturbation of physical quantities in the framework of general relativity: one is direct, the other is geometrical. Correspondingly, there are two types of gauge transformation related with these two definitions. The passive approach is based on the property of general covariance, and the active one is through the action of Lie-derivative. Although under a proper coordinate choice, the two approaches seem to agree with each other, they are different in nature. The geometrical definition of relativistic perturbation and the active approach for gauge transformation are more rigorous in mathematics and less confusing in physical explanation. The direct definition, however, seems to be plagued with difficulties in physical meaning, and the passive approach is more awkward to use, especially for high-order gauge transformations.
基金the National Natural Science Foundation of China (No. 10871192) and the Natural Science Foundation of Hebei Province (No. A2007000138).
文摘In this paper we mainly study derivation algebras of n-Lie algebras. We give the detailed structural description of derivation algebras of n + 1 dimensional n-Lie algebras over the real field.
基金supported by National Natural Science Foundation of China(Grant Nos.11026046,11101179,10971071)Doctoral Fund of Ministry of Education of China(Grant No.20100061120096)the Fundamental Research Funds for the Central Universities(Grant No.200903294)
文摘In this paper,we give the notion of derivations of Lie 2-algebras using explicit formulas,and construct the associated derivation Lie 3-algebra.We prove that isomorphism classes of non-abelian extensions of Lie 2-algebras are classified by equivalence classes of morphisms from a Lie 2-algebra to a derivation Lie 3-algebra.