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Sections of the vector bundle

  1. Feb 15, 2013 #1
    Hi Friends :))
    my little problem is :
    Let E be a vector bundle over a manifold M, and (s_ {1}, ......, s_ {n}) a family of sections of E. This family is generating bundle E, ​​ that is for every point x in M, (s_ {1} (x), ......, s_ {n} (x)) is generator of the vector space E_{x} ? is that we have only (s_ {1} (x1), ......, s_ {n} (x1)) is a generator of E_ {x1} and (s_ {1} (x 2), .. ...., s_ {n} (x2)) is not generating E_ {x2}??
    Thank you for making me understand this confusion on sections of a vector bundle generator ...
     
  2. jcsd
  3. Feb 15, 2013 #2

    lavinia

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    A set of sections may be lineally independent at one point but not another. It cannot span the fiber above a point where they are not linearly independent.

    But over any point where there are n linearly independent sections they span the fiber. Over another point where they are independent they also space the fiber. That means that on that fiber some linear combination of the sections equals any v.

    But more is true: they simultaneously span all of the fibers where they from a basis. Can you prove this?
     
  4. Feb 16, 2013 #3
    My problem is: if a family of sections generate E_ {x1}? is that this family engandrent E_ {x2} or any other fiber, or a family of sections if (free generator, form a basis ....) is that above all point x variety, (S_{1}, ....,s_{n}) are kept the same properties?
     
  5. Feb 18, 2013 #4

    lavinia

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    Read my post carefully.
     
  6. Feb 18, 2013 #5
    If I understand what you mean, a family of sections can be generating a vector bundle at a point that if they are linearly independent
    "" It cannot span the fiber above a point where they are not linearly independent. ""
     
  7. Feb 18, 2013 #6

    lavinia

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    What about the last sentence in the post?
     
  8. Feb 18, 2013 #7
    you said " But over any point where there are n linearly independent sections they span the fiber. Over another point where they are independent they also space the fiber " . you want to say dependent, they also generate the vector bundle ?
     
  9. Feb 18, 2013 #8

    lavinia

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    I said

    But more is true: they simultaneously span all of the fibers where they from a basis. Can you prove this?
     
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