An invertible sheaf on a scheme over a field is called very ample if (1) at each point , there is a global section not vanishing at , and (2) for each pair of points , there is a global section such that vanishes at exactly one of and .
If is algebraically closed, Riemann-Roch (http://planetmath.org/RiemannRochTheorem) shows that on a curve , any invertible sheaf of degree greater than or equal to twice the genus of is very ample.
|Date of creation||2013-03-22 13:52:44|
|Last modified on||2013-03-22 13:52:44|
|Last modified by||Mathprof (13753)|