Given a symmetric divisor D on M0,n, this function returns the list of symmetric F curves C such that D . C=0.
Here is an example from the paper [AGSS]: When n is even, the divisor Dn1,n/2 is zero on even F-curves and 1 on odd F-curves. (Here the parity of Fa,b,c,d is defined to be the parity of the product abcd.) In the calculations below, we check this claim for n=8.
i1 : D=symmetricDivisorM0nbar(8,3*B_2+2*B_3+4*B_4) o1 = SymmetricDivisorM0nbar{2 => 3 } 3 => 2 4 => 4 NumberOfPoints => 8 o1 : SymmetricDivisorM0nbar |
i2 : killsCurves(D) o2 = {{4, 2, 1, 1}, {3, 2, 2, 1}, {2, 2, 2, 2}} o2 : List |