Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-19T15:18:07.694Z Has data issue: false hasContentIssue false

XXII.—Tensor Fields and Connections on Cross-Sections in the tangent bundle of a differentiable manifold*

Published online by Cambridge University Press:  14 February 2012

Kentaro Yano
Affiliation:
University of Aberdeen†

Synopsis

Tensor fields and linear connections in an n-dimensional differentiable manifold M can be extended, in a natural way, to the tangent bundle T(M) of M to give tensor fields of the same type and linear connections in T(M) respectively. We call such extensions complete lifts to T(M) of tensor fields and linear connections in M.

On the other hand, when a vector field V is given in M, V determines a cross-section which is an n-dimensional submanifold in the 2n-dimensional tangent bundle T(M).

We study first the behaviour of complete lifts of tensor fields on such a cross-section. The complete lift of an almost complex structure being again an almost complex structure, we study especially properties of the cross-section as a submanifold in an almost complex manifold.

We also study properties of cross-sections with respect to the linear connection which is the complete lift of a linear connection in M and with respect to the linear connection induced by the latter on the cross-section. To quote a typical result: A necessary and sufficient condition for a cross-section to be totally geodesic is that the vector field V in M defining the cross-section in T(M) be an affine Killing vector field in M.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1967

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

References to Literature

Newlander, A. and Nirenberg, L., 1957. “Complex analytic co-ordinates in almost complex manifolds”, Ann. Math., Princeton, 65, 391404.CrossRefGoogle Scholar
Nijenhuis, A., 1951. “Xn−1 forming sets of eigenvectors”. Ind. Math., 13, 200212.CrossRefGoogle Scholar
Sato, I., 1965. “Almost analytic vector fields in almost complex manifolds”. Tohoku Math. J., 17, 185199.CrossRefGoogle Scholar
Schouten, J. A. and Yano, K., 1955. “On invariant subspaces in the almost complex X2n”. Ind. Math., 17, 261269.CrossRefGoogle Scholar
Yano, K., 1957. Theory of Lie derivatives and its applications. North-Holland Pubi. Co.Google Scholar
Yano, K., 1965. Differential geometry on complex and almost complex spaces, Pergamon Press.Google Scholar
Yano, K. and Kobayashi, S., 1966. “Prolongations of tensor fields and connections to tangent bundles I”. J. Math. Soc. Japan, 18, 194210.Google Scholar
Yano, K. and Ledger, A. J., 1964. “Linear connections on tangent bundles”, J. Lond. Math. Soc., 39, 495500.CrossRefGoogle Scholar