On the dimension of Lie algebras of infinitesimal affine transformations of direct products of more than two spaces of affine connection of the first type
Abstract
The theory of motions in generalized spaces is one of the directions in modern differential geometry. Such scientists as E. Cartan, P. K. Rashevsky, P. A. Shirokov, I. P. Egorov, A.Ya. Sultanov and other scientists were engaged in the study of movements in various spaces of affine connections. The question of movements in direct products of two spaces of affine connection was considered in M. V. Morgun’s work.
In the case of a direct product of more than two spaces of affine connection, the question of the dimension of Lie algebras of infinitesimal affine transformations of a given space remained open.
In this article, an estimate of the upper bound of the dimension of the Lie algebra of infinitesimal affine transformations of affine connection spaces, representing a direct reproduction of at least three non-projective Euclidean spaces of a certain type, is obtained.
To solve this problem, a system of linear homogeneous equations is obtained, which is satisfied by the components of an arbitrary infinitesimal affine transformation. This system is found using the properties of the Lie derivative applied to the tensor field of curvature of the spaces under consideration. The evaluation of the rank of this system allows us to obtain an estimate from below of the rank of the matrix of the system under consideration.
Reference
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