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I am reading John M. Lee's book: Introduction to Smooth Manifolds ...
I am focused on Chapter 3: Tangent Vectors ...
I need some help in fully understanding Lee's conversation on computations with tangent vectors and pushforwards ... in particular I need clarification on the nature of the 'vectors' [itex]\partial / \partial x_i |_p [/itex] ... ...
The relevant conversation in Lee is as follows:
In the above text from Lee we read the following:
" .. ... The vectors [itex]\partial / \partial x_i |_p [/itex] are called the coordinate vectors at [itex]p[/itex] associated with a given coordinate system ... ... "
My question is as follows:
How or in what sense are the [itex]\partial / \partial x_i |_p [/itex] vectors ... they are certainly not objects with a magnitude and direction ... they seem to me to be maps or operators ... ...
Indeed they are defined by Lee as follows:
[itex]\frac{ \partial }{ \partial x^i } |_p = ( \phi^{-1}_* ) \frac{ \partial }{ \partial x^i } |_{\phi(p)} [/itex]Thus, the [itex]\frac{ \partial }{ \partial x^i } |_p[/itex] are mappings ... put in a smooth function [itex]f[/itex] and get out a real number ...
So ... how, or in what sense are these objects vectors ...
Hope someone can clarify this issue ...
Peter
I am focused on Chapter 3: Tangent Vectors ...
I need some help in fully understanding Lee's conversation on computations with tangent vectors and pushforwards ... in particular I need clarification on the nature of the 'vectors' [itex]\partial / \partial x_i |_p [/itex] ... ...
The relevant conversation in Lee is as follows:
In the above text from Lee we read the following:
" .. ... The vectors [itex]\partial / \partial x_i |_p [/itex] are called the coordinate vectors at [itex]p[/itex] associated with a given coordinate system ... ... "
My question is as follows:
How or in what sense are the [itex]\partial / \partial x_i |_p [/itex] vectors ... they are certainly not objects with a magnitude and direction ... they seem to me to be maps or operators ... ...
Indeed they are defined by Lee as follows:
[itex]\frac{ \partial }{ \partial x^i } |_p = ( \phi^{-1}_* ) \frac{ \partial }{ \partial x^i } |_{\phi(p)} [/itex]Thus, the [itex]\frac{ \partial }{ \partial x^i } |_p[/itex] are mappings ... put in a smooth function [itex]f[/itex] and get out a real number ...
So ... how, or in what sense are these objects vectors ...
Hope someone can clarify this issue ...
Peter