2025-09-21

1312: Rank of \(C^\infty\) Map Between \(C^\infty\) Manifolds with Boundary at Point

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definition of rank of \(C^\infty\) map between \(C^\infty\) manifolds with boundary at point

Topics


About: \(C^\infty\) manifold

The table of contents of this article


Starting Context



Target Context


  • The reader will have a definition of rank of \(C^\infty\) map between \(C^\infty\) manifolds with boundary at point.

Orientation


There is a list of definitions discussed so far in this site.

There is a list of propositions discussed so far in this site.


Main Body


1: Structured Description


Here is the rules of Structured Description.

Entities:
\( M_1\): \(\in \{\text{ the } C^\infty \text{ manifolds with boundary } \}\)
\( M_2\): \(\in \{\text{ the } C^\infty \text{ manifolds with boundary } \}\)
\( f\): \(: M_1 \to M_2\), \(\in \{\text{ the } C^\infty \text{ maps }\}\)
\( m\): \(\in M_1\)
\( d f_m\): \(: T_mM_1 \to T_{f (m)}M_2\), \(= \text{ the differential of } f \text{ at } m\)
\(*Rank (f)_m\): \(= Rank (d f_m)\)
//

Conditions:
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2: Note


In general, the rank of \(f\) changes point to point.

When the rank of \(f\) is the same at all the points of \(M_1\), \(f\) is called to have "constant rank".

When at each point of \(M_1\), there is a neighborhood of the point over which \(f\) has the same rank, \(f\) is called to have "locally constant rank".


References


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