ABSTRACT
Let c/ == (P, f/J) be an element of ap-chain on M, where PeR p is a closed interval and f/J is a differentiable mapping ofan open U c Pinto M
Let c == 'Lk,c, be a corresponding chain. /
We know to a vector field X correspond curves (called orbits): t H lfI/x
that are solutions ofthe differential system:
cIx' == X' (Xl ,...,xn ). dt
(7-11)
One says these orbits form a "tube. " More precisely, given an open f/J(U) ofM, the mapping
I(c R) x f/J(U) ~M: (t,x) ~ 'fItX
assigns to any point x of the support c a point 'fItX of the curve (orbit) t ~ 'fItX passing through 'fIo(x) =x.